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Pearl S, Anbarasu A. Genomic landscape of nosocomial Acinetobacter baumannii: A comprehensive analysis of the resistome, virulome, and mobilome. Sci Rep 2025; 15:18203. [PMID: 40414962 DOI: 10.1038/s41598-025-03246-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2025] [Accepted: 05/19/2025] [Indexed: 05/27/2025] Open
Abstract
Acinetobacter baumannii (A. baumannii) is a major multidrug-resistant pathogen, posing serious threats in the healthcare settings. This study provides a comprehensive genomic analysis of nosocomial A. baumannii whole-genome sequences retrieved from NCBI Genome database. Multilocus sequence typing and capsule typing were performed to investigate the clonal diversity. The genomes were characterized to identify antimicrobial resistance genes (ARGs), virulence factors, and mobile genetic elements. Further, pangenome analysis was conducted to examine the core and accessory genomes of A. baumannii. Our dataset comprised of 609 genomes deposited from diverse geographic regions worldwide between 2004 and 2024. The genomes showed high clonal heterogeneity, with sequence type ST2 being the predominant sequence type. A total of 185 unique ARGs were identified, with majority of them associated with efflux pump and β-lactamase coding genes. Over 25,000 IS elements were detected, with IS4 family being the prevalent type. High abundance of integron-mediated resistance determinants, especially for aminoglycosides and β-lactams, were identified. The open pangenome window due to its larger accessory genome suggested substantial genome plasticity. Our findings highlight A. baumannii's rapid evolution and resistance potential, emphasizing need for alternative therapeutic strategies. Enhanced surveillance, infection control measures, and antimicrobial stewardship are crucial to combat this persistent threat.
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Affiliation(s)
- Sara Pearl
- Department of Biotechnology, School of Biosciences and Technology (SBST), Vellore Institute of Technology (VIT), Vellore, 632014, India
- Medical and Biological Computing Laboratory, School of Biosciences and Technology (SBST), Vellore Institute of Technology (VIT), Vellore, 632014, India
| | - Anand Anbarasu
- Department of Biotechnology, School of Biosciences and Technology (SBST), Vellore Institute of Technology (VIT), Vellore, 632014, India.
- Medical and Biological Computing Laboratory, School of Biosciences and Technology (SBST), Vellore Institute of Technology (VIT), Vellore, 632014, India.
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2
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Koong J, Hall RM, Hamidian M. Genomic characteristics of the multiresistant Acinetobacter baumannii global clone 1 reference strain A297/RUH875. J Antimicrob Chemother 2025:dkaf160. [PMID: 40387539 DOI: 10.1093/jac/dkaf160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2025] [Accepted: 05/09/2025] [Indexed: 05/20/2025] Open
Abstract
OBJECTIVES Acinetobacter baumannii ST1, also known as global clone 1 (GC1), is a globally distributed lineage associated with antimicrobial resistance (AMR). The multiresistant isolate A297/RUH8751, recovered from a urinary tract infection in the Netherlands in 1984, has served as a reference strain for ST1. We aimed to generate and analyse the complete genome sequence of A297/RUH8751 to provide insights into its genomic features, antibiotic resistance determinants and phylogenetic placement. METHODS WGS was performed using Oxford Nanopore GridION and Illumina HiSeq platforms. Assembly was conducted with Autocycler v0.2.1. Genomic features, including antibiotic resistance genes, insertion sequences and restriction-modification systems, were characterized using ResFinder, ISFinder and REBASE. Comparative analyses were conducted with the draft genome of NIPH 527, which also represents RUH875, to assess sequence variations. Phylogenetic analysis was performed to determine the evolutionary placement of A297/RUH875 within GC1. RESULTS The complete genome of RUH875 (A297) consists of a 3 965 450 bp chromosome and three plasmids: pA297-1 (pRAY*; 6078 bp), pA297-2 (8731 bp) and pA297-3 (a 200 kb conjugative plasmid). The chromosome harbours the AbaR21 genomic resistance island, carrying seven antibiotic resistance genes and six prophage regions. Notably, bap1 and bap2, biofilm-associated genes, were fully resolved, with bap1 identical to that of A. baumannii A1-the earliest GC1 isolate. Comparative analysis with A1 revealed 122 SNPs, with clustered variations suggesting potential recombination events. Phylogenetic analysis confirmed A297/RUH875 as a distinct lineage within GC1. The completed genome sequence provides a reference, in addition to strain A1, for studying AMR evolution in GC1 and enhances comparative genomic analyses.
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Affiliation(s)
- Jonathan Koong
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Ruth M Hall
- School of Life and Environmental Sciences, The University of Sydney, NSW 2006, Australia
| | - Mehrad Hamidian
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, NSW 2007, Australia
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3
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Scarrone M, Turner D, Dion M, Tremblay D, Moineau S. In silico and in vitro comparative analysis of 79 Acinetobacter baumannii clinical isolates. Microbiol Spectr 2025:e0284924. [PMID: 40377313 DOI: 10.1128/spectrum.02849-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2024] [Accepted: 04/08/2025] [Indexed: 05/18/2025] Open
Abstract
Acinetobacter baumannii is a significant nosocomial bacterial pathogen that poses a substantial infection risk due to its high resistance to antibiotics and ability to survive in hospital environments. In this study, we performed comprehensive in silico and in vitro analyses on 79 A. baumannii clinical isolates from different geographical locations to uncover their genomic and epidemiological characteristics as well as their antibiotic and phage susceptibilities. Our findings revealed considerable genomic diversity among the isolates, as shown by average nucleotide identity (ANI) heat maps, multilocus sequence typing (MLST), and core genome MLST (cgMLST). We identified several international clones known for their high antibiotic resistance and global prevalence. Surprisingly, we also observed that the number of antimicrobial resistance genes (ARGs) was higher in isolates containing CRISPR-Cas systems. Plaque assays with 13 phages indicated that Acinetobacter phages have a narrow host range, with capsule loci (KL) serving as a good indicator of phage-bacteria interactions. The presence of CRISPR-Cas systems and other antiviral defense mechanisms in A. baumannii genomes also appears to play a key role in providing phage resistance, regardless of the phage receptors. We also found that spacers associated with subtypes I-F1 and I-F2 CRISPR-Cas systems predominantly target prophages, suggesting a role in maintaining genomic stability and contributing to phage-bacteria co-evolution. Overall, this study provides a set of highly characterized A. baumannii clinical isolates for future studies on antibiotic-phage-bacteria interactions.IMPORTANCEAcinetobacter baumannii poses a significant challenge to the healthcare system due to its antibiotic resistance and strong survival mechanisms. This study examines a diverse collection of 79 clinical isolates to deepen our understanding of A. baumannii's genetic characteristics and its defense mechanisms against both antibiotics and phages. Genomic analysis revealed globally prevalent, highly resistant clones and uncovered a complex role for CRISPR-Cas systems. Although CRISPR-Cas systems were not widespread among these isolates, they primarily targeted prophages. Additionally, the study emphasizes the importance of capsule types as indicators of phage susceptibility. Together, these findings provide insights into the pathogen's resilience and evolutionary adaptations, potentially guiding future research on infection control strategies and new therapeutic approaches to combat A. baumannii infections.
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Affiliation(s)
- Martina Scarrone
- Département de biochimie, de microbiologie et de bio-Informatique, Faculté des sciences et de génie, Université Laval, Quebec City, Quebec, Canada
- Institut de biologie intégrative et des systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
| | - Dann Turner
- School of Applied Sciences, College of Health, Science and Society, University of the West of England, , Bristol, United Kingdom
| | - Moïra Dion
- Département de biochimie, de microbiologie et de bio-Informatique, Faculté des sciences et de génie, Université Laval, Quebec City, Quebec, Canada
| | - Denise Tremblay
- Département de biochimie, de microbiologie et de bio-Informatique, Faculté des sciences et de génie, Université Laval, Quebec City, Quebec, Canada
- Institut de biologie intégrative et des systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses, Université Laval, Quebec City, Quebec, Canada
| | - Sylvain Moineau
- Département de biochimie, de microbiologie et de bio-Informatique, Faculté des sciences et de génie, Université Laval, Quebec City, Quebec, Canada
- Institut de biologie intégrative et des systèmes (IBIS), Université Laval, Quebec City, Quebec, Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses, Université Laval, Quebec City, Quebec, Canada
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Yehya A, Ezzeddine Z, Chakkour M, Dhaini Z, Bou Saba MS, Bou Saba AS, Nohra L, Nassar NB, Yassine M, Bahmad HF, Ghssein G. The intricacies of Acinetobacter baumannii: a multifaceted comprehensive review of a multidrug-resistant pathogen and its clinical significance and implications. Front Microbiol 2025; 16:1565965. [PMID: 40444001 PMCID: PMC12121509 DOI: 10.3389/fmicb.2025.1565965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2025] [Accepted: 04/07/2025] [Indexed: 06/02/2025] Open
Abstract
Acinetobacter baumannii, a highly adaptive and formidable nosocomial pathogen, has emerged as a symbol of modern medicine's struggle against multidrug resistance (MDR). As a Gram-negative dweller in moist hospital environments, A. baumannii has proven its ability to colonize the most vulnerable-critically ill patients-leaving behind a trail of infections highlighted by high morbidity and mortality and rendering nearly all antibiotics ineffective. This literature review aims to provide an in-depth, comprehensive overview of microbiological features, virulence factors, clinical manifestations, epidemiology, and antibiotic resistance mechanisms of A. baumannii. It also highlights the different diagnostic approaches, possible treatment strategies, and infection control, as well as the profound public health burden this pathogen imposes. The genus Acinetobacter has undergone a pivotal taxonomic journey and categorization. In addition, the intricate virulence mechanisms and factors of A. baumannii, including but not limited to outer membrane components and nutrient acquisition systems, have contributed to its pathogenicity and severe clinical manifestations ranging from respiratory tract infections and meningitis to urinary tract infections, skin infections, and bloodstream infections. This review also describes the epidemiological trend of A. baumannii established by its global prevalence and distribution, risk factors, hospital-acquired vs. community-acquired infections, and its geographical variations. In terms of antibiotic resistance, this pathogen has demonstrated resilience to a wide range of first-line and last-resort antibiotics due to its different evasion mechanisms. The current diagnostic approaches, treatment strategies, and infection control measures are further analyzed in detail, underscoring the need for prompt and precise identification of A. baumannii to guide appropriate therapy and reinforce the optimal approaches to limit its transmission and control outbreaks. Finally, the review addresses the substantial public health implications, reflecting on the hindrance that A. baumannii brings to healthcare systems, and the urgent need for global surveillance, effective infection control protocols, innovative research, and therapeutic approaches to mitigate its global threat.
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Affiliation(s)
- Amani Yehya
- Department of Anatomy, Cell Biology, and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Zeinab Ezzeddine
- High Council for Scientific Research and Publication (HCSRP), Islamic University of Lebanon (IUL), Khalde, Lebanon
| | - Mohamed Chakkour
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - Zahraa Dhaini
- Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| | | | | | - Lea Nohra
- Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| | - Nagham B. Nassar
- Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| | - Mahdi Yassine
- Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| | - Hisham F. Bahmad
- Department of Pathology and Laboratory Medicine, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Ghassan Ghssein
- High Council for Scientific Research and Publication (HCSRP), Islamic University of Lebanon (IUL), Khalde, Lebanon
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Tian C, Zhao Y, Dong S, You Z, Chen J, Xu H, Fang Y, Zhang Y. Emergence and characterization of a ST852 Klebsiella quasipneumoniae clinical isolate coharboring bla NDM-1 and bla KPC-2 in China. Front Cell Infect Microbiol 2025; 15:1564277. [PMID: 40415960 PMCID: PMC12098455 DOI: 10.3389/fcimb.2025.1564277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2025] [Accepted: 04/21/2025] [Indexed: 05/27/2025] Open
Abstract
Objectives To characterize a rare ST852 Klebsiella quasipneumoniae strain co-producing NDM-1 and KPC-2 isolated from a clinical patient. Methods Minimum inhibitory concentrations (MICs) were measured using a VITEK 2 compact system and broth microdilution. Conjugation experiments were conducted using film matings. Whole genome sequencing (WGS) was performed using Illumina and Nanopore platforms. Antimicrobial resistance determinants were identified using the ABRicate program in the ResFinder database. Insertion sequences (ISs) were identified using ISFinder. Bacterial virulence factors were identified using a virulence factor database (VFDB). Genome function annotation and classification were further analyzed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Cluster of Orthologous Groups (COG) databases. Capsular polysaccharides (KL) and lipooligosaccharides (OCL) were tested using Kleborate with the Kaptive. Multilocus sequence typing (MLST) and replicon types were identified using the Center for Genomic Epidemiology website. Prophage region analysis was performed using PHASTEST software. Conjugation-related elements were predicted using oriTfinder. The plasmid structure was visualized using Circos and similar plasmids in the public database were tracked using BacWGSTdb. A global phylogeny for the ST852 K. quasipneumoniae isolates was further performed. Results K. quasipneumoniae KPSY isolate was identified as ST852, with KL18 and O3/O3a. It has an extensive drug-resistant (XDR) profile. WGS analysis revealed that it contained one circular chromosome and three plasmids. The results of the COG and KEGG functional classifications showed that most of the functions were associated with metabolism. pKPSY-2 is a 239,226-bp IncU plasmid carrying the carbapenem resistance gene bla NDM-1. pKPSY-3 is a smaller plasmid belonging to the IncN-type conjugative plasmid with bla KPC-2. Importantly, oriT sequence, the T4SS region, T4CP, and relaxase were identified. Tracking of the bla KPC-2 plasmids showed they were identified in different species in different countries, including E. coli, Leclercia sp., Pantoea sp., and E. hormaechei. Global analysis data showed 13 ST852 strains were mainly isolated from China (84.62%, 11/13), and the remaining isolates were collected from Switzerland. Conclusions This is the first study to identify an ST852 NDM-1-KPC-2 coproducing K. quasipneumoniae clinical isolate. Surveillance is warranted, and early detection of this high-risk clone in the clinic is recommended to avoid its extensive spread.
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Affiliation(s)
- Chongmei Tian
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Yaping Zhao
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Su Dong
- Department of Clinical Laboratory, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Zhixin You
- Department of Respiratory Medicine, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Jingbai Chen
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Hongfeng Xu
- Pharmacy Department of Chinese Medicine, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China
| | - Yuejuan Fang
- Department of Pharmacy, Quzhou Maternal and Child Health Care Hospital, Quzhou, China
| | - Yapei Zhang
- Department of Clinical Laboratory, Zhejiang Hospital, Hangzhou, Zhejiang, China
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Sharar NS, Iovine A, De Castro C, Hall RM, Kenyon JJ. Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid. Commun Biol 2025; 8:700. [PMID: 40325156 PMCID: PMC12053666 DOI: 10.1038/s42003-025-08114-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2024] [Accepted: 04/22/2025] [Indexed: 05/07/2025] Open
Abstract
The nonulosonic acid 8-epipseudaminic acid was discovered only recently in two Acinetobacter baumannii strains but the genes responsible for conversion of pseudaminic acid to its 8-epimer were not found at the K locus. Here, we use a pan-genome approach to identify a pair of carbohydrate biosynthesis genes, epaA and epaB, and demonstrate using NMR analysis of the capsular polysaccharide that they encode enzymes able to convert pseudaminic acid to its 8-epimer. Via an extensive survey of available A. baumannii genomes, we show that the epaA and epaB genes are present in 17 different Caudoviricetes class prophages. The prophages are in genomes that carry different capsule biosynthesis loci from isolates recovered in several different countries. The presence of epaA and epaB genes in A. baumannii isolates that are able to produce pseudaminic acid leads to modification of capsular polysaccharides that decorate their cell surface with potential implications for capsule typing and capsule-targeting therapies.
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Affiliation(s)
- Nowshin S Sharar
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
| | - Andrea Iovine
- Department of Chemical Sciences, University of Napoli Federico II Complesso Universitario Monte Santangelo, Via Cintia 4, I-80126, Naples, Italy
| | - Cristina De Castro
- Department of Chemical Sciences, University of Napoli Federico II Complesso Universitario Monte Santangelo, Via Cintia 4, I-80126, Naples, Italy
| | - Ruth M Hall
- School of Life and Environmental Science, The University of Sydney, Sydney, NSW, Australia.
| | - Johanna J Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia.
- School of Pharmacy and Medical Sciences, Health Group, Griffith University, Gold Coast Campus, Southport, QLD, Australia.
- Institute for Biomedicine and Glycomics, Griffith University, Gold Coast Campus, Southport, QLD, Australia.
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Fernández-Cuenca F, Rodríguez-Pallares S, López-Cerero L, Gutiérrez-Fernández J, Bautista MF, Sánchez Gómez JA, Sánchez-Yebra Romera W, Delgado M, Recacha E, Pascual A. Regional distribution of carbapenemase-producing Acinetobacter baumannii isolates in southern Spain (Andalusia). Eur J Clin Microbiol Infect Dis 2025; 44:1069-1076. [PMID: 39961948 PMCID: PMC12062160 DOI: 10.1007/s10096-025-05047-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2024] [Accepted: 01/16/2025] [Indexed: 05/09/2025]
Abstract
OBJECTIVES This is the first study conducted in southern Spain to determine i) the population structure (PS) of carbapenem-resistant (CR) Acinetobacter baumannii isolates by multilocus sequencing typing (MLST) and core genome MLST (cgMLST) and ii) the association between the sequence type ST and the blaOXA-51 variant, capsule polysaccharide locus (KL) and lipooligosaccharide outer core locus (OCL) types. METHODS Of 336 isolates submitted to the Andalusian reference laboratory (PIRASOA; December 2017-2020), 73 were subjected to WGS (MiSeq). The following analyses were performed: bacterial identification (ribosomal MLST), carbapenemase gene detection (Resfinder 4.0), PS delineation (MLST by MLSTfinder 2.0 and cgMLST by Ridom SeqSphere+), and KL types and OCL types (Kaptive tool). RESULTS The carbapenemases detected were blaOXA-23 (n = 41), blaOXA-58 (n = 26), blaOXA-24 (n = 5), blaOXA-72 (n = 1) and blaNDM-1 (n = 2). The PS revealed one major ST2 clone (n = 54) and seven minor ST clones by MLST, and 41 lineages by cgMLST. Thirty-five lineages were detected only in a single hospital whereas five lineages were observed in several hospitals and provinces. blaOXA-66 was the most frequent blaOXA-51 variant and was mainly associated with the ST2 clone. Eleven KL types and 3 OCL types were assigned, with KL2 (n = 27), KL7 (n = 16) and OCL1 being the most frequent. CONCLUSIONS The PS of CR A. baumannii in Andalusia is characterized by a dominant ST2/blaOXA-23 clone and several lineages, showing local spread of lineages in most hospitals, and intercenter or interregional spread of a few lineages. Single-locus blaOXA-51-like typing and KL typing may be useful as complementary preliminary typing tool.
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Affiliation(s)
- Felipe Fernández-Cuenca
- University Hospital Virgen Macarena, Seville, Spain
- Institute of Biomedicine of Seville, Seville, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Salud Rodríguez-Pallares
- Servicio de Microbiología e Instituto de Investigación Biomédica A Coruña (INIBIC), Complexo Hospitalario Universitario A Coruña, A Coruña, Spain
| | - Lorena López-Cerero
- University Hospital Virgen Macarena, Seville, Spain.
- Institute of Biomedicine of Seville, Seville, Spain.
- University of Seville, Seville, Spain.
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain.
| | | | | | | | | | - Mercedes Delgado
- University Hospital Virgen Macarena, Seville, Spain
- Institute of Biomedicine of Seville, Seville, Spain
- University of Seville, Seville, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Esther Recacha
- University Hospital Virgen Macarena, Seville, Spain
- Institute of Biomedicine of Seville, Seville, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Alvaro Pascual
- University Hospital Virgen Macarena, Seville, Spain
- Institute of Biomedicine of Seville, Seville, Spain
- University of Seville, Seville, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
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Luo Q, Chang M, Lu P, Guo Q, Jiang X, Xiao T, Zhang H, Ma Y, Zhang Y, Yu W, Zhang E, Chen Y, Shen P, Ji J, Ying C, Liu Z, Zhu H, Xiao Y. Genomic epidemiology and phylodynamics of Acinetobacter baumannii bloodstream isolates in China. Nat Commun 2025; 16:3536. [PMID: 40229304 PMCID: PMC11997098 DOI: 10.1038/s41467-025-58772-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2024] [Accepted: 04/01/2025] [Indexed: 04/16/2025] Open
Abstract
In recent decades, Acinetobacter baumannii has become a major global nosocomial pathogen, with bloodstream infections (BSIs) exhibiting mortality rates exceeding 60% and imposing substantial economic burdens. However, limited large-scale genomic epidemiology has hindered understanding of its population dynamics. Here, we analyzed 1506 non-repetitive BSI-causing A. baumannii isolates from 76 Chinese hospitals over a decade (2011-2021). We identified 149 sequence types (STs) and 101 K-locus types (KLs), revealing increased population diversity. International clone (IC) 2 accounted for 81.74% of isolates, with a notable shift in prevalent STs: ST208 increased while ST191 and ST195 declined, aligning with global trends. ST208 exhibited higher virulence, greater antibiotic resistance, enhanced desiccation tolerance, and more complex transmission patterns compared to ST191 and ST195. Its genomic plasticity drives its adaptation and spread. Using the high-resolution Oxford MLST scheme, this study uncovered greater diversity and genetic factors behind ST208's rise. A. baumannii is evolving from a low-virulence, multidrug-resistant pathogen to a more virulent one, highlighting the urgent need to address its growing threat. These findings have critical implications for infection control and public health policies.
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Affiliation(s)
- Qixia Luo
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Mengru Chang
- Department of Biomedical Engineering, College of Future Technology, Center for Quantitative Biology, and Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Ping Lu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Qian Guo
- Department of Biomedical Engineering, College of Future Technology, Center for Quantitative Biology, and Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Xiaoqing Jiang
- Department of Biomedical Engineering, College of Future Technology, Center for Quantitative Biology, and Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Tingting Xiao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Haoyu Zhang
- Department of Biomedical Engineering, College of Future Technology, Center for Quantitative Biology, and Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Yingying Ma
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Yan Zhang
- Department of Biomedical Engineering, College of Future Technology, Center for Quantitative Biology, and Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Wei Yu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Erjia Zhang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Yunbo Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Ping Shen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Jinru Ji
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Chaoqun Ying
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Zhiying Liu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China
| | - Huaiqiu Zhu
- Department of Biomedical Engineering, College of Future Technology, Center for Quantitative Biology, and Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.
| | - Yonghong Xiao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, the First Affiliated Hospital of Medical School, College of medicine, Zhejiang University, Hangzhou, China.
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Shi J, Mao X, Sun F, Cheng J, Shao L, Shan X, Zhu Y. Epidemiological characteristics and antimicrobial resistance of extensively drug-resistant Acinetobacter baumannii in ICU wards. Microbiol Spectr 2025; 13:e0261924. [PMID: 40035537 PMCID: PMC11960075 DOI: 10.1128/spectrum.02619-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2024] [Accepted: 01/08/2025] [Indexed: 03/05/2025] Open
Abstract
Acinetobacter baumannii is a significant nosocomial pathogen, particularly problematic due to its extensive drug resistance. This study investigates 56 extensively drug-resistant A. baumannii (XDRAB) strains collected from various ICU wards at Jinhua Central Hospital, Zhejiang Province, China. Strains were isolated from diverse clinical samples, including sputum, blood, cerebrospinal fluid, and wound secretions. Identification was confirmed via matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), and antibiotic susceptibility testing was conducted using the VITEK 2 Compact system, E-test, and Kirby-Bauer methods. All strains were susceptible to polymyxin, with four showing intermediate susceptibility to tigecycline, while resistance rates to other antibiotics were 100%. Molecular typing through pulsed-field gel electrophoresis (PFGE) classified the strains into 10 types, with the dominant type (G) primarily found in ICU3, indicating a potential clonal outbreak. Whole-genome sequencing (WGS) and multi-locus sequence typing (MLST) identified ST208 as the predominant sequence type. Resistance gene screening revealed the presence of blaOXA-23, blaTEM-1D, and aminoglycoside resistance genes in most strains. Phylogenetic analysis confirmed the clonal transmission of ST208 strains across the hospital, with a high degree of genomic similarity among the isolates. These findings highlight the importance of continuous monitoring and effective infection control measures to prevent the spread of XDRAB in healthcare settings.IMPORTANCEExtensively drug-resistant Acinetobacter baumannii is a critical public health threat, particularly in hospital environments where it causes a variety of infections. The global spread of extensively drug-resistant A. baumannii (XDRAB) and its resistance to most antibiotics make treatment options limited, increasing the risk of patient morbidity and mortality. This study provides important insights into the molecular epidemiology of XDRAB in a hospital setting, revealing the clonal transmission of the ST208 sequence type. By utilizing both pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS), we identified genetic links between strains and the presence of key resistance genes. The findings underscore the urgent need for robust infection control protocols, routine surveillance, and judicious use of antibiotics to mitigate the spread of XDRAB and ensure better patient outcomes.
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Affiliation(s)
- Jingchao Shi
- Department of Clinical Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine (Jinhua Municipal Central Hospital), Jinhua, Zhejiang, China
| | - Xiaoting Mao
- Department of Clinical Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine (Jinhua Municipal Central Hospital), Jinhua, Zhejiang, China
- Department of Clinical Laboratory, Jinhua Maternal and Child Health Care Hospital, Jinhua, Zhejiang, China
| | - Fengtian Sun
- Department of Clinical Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine (Jinhua Municipal Central Hospital), Jinhua, Zhejiang, China
| | - Jianghao Cheng
- Department of Clinical Laboratory, Zhejiang Cancer Hospital, Hangzhou, Zhejiang, China
| | - Lijia Shao
- Department of Clinical Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine (Jinhua Municipal Central Hospital), Jinhua, Zhejiang, China
| | - Xiaoyun Shan
- Department of Clinical Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine (Jinhua Municipal Central Hospital), Jinhua, Zhejiang, China
| | - Yijun Zhu
- Department of Clinical Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine (Jinhua Municipal Central Hospital), Jinhua, Zhejiang, China
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Tobin LA, Abu Sabah E, Lebreton F, Myers GSA, McGann PT, Hamidian M. Genomic analysis of early ST32 Acinetobacter baumannii strains recovered in US military treatment facilities reveals distinct lineages and links to the origins of the Tn6168 ampC transposon. J Antimicrob Chemother 2025; 80:666-675. [PMID: 39680383 PMCID: PMC11879209 DOI: 10.1093/jac/dkae454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2024] [Accepted: 12/02/2024] [Indexed: 12/17/2024] Open
Abstract
OBJECTIVES To study the population structure and genomic characteristics, including antimicrobial resistance genes, plasmid types and surface polysaccharide type, of the globally distributed Acinetobacter baumannii belonging to ST32 (Institut Pasteur scheme). METHODS Antibiotic resistance phenotype for 19 antibiotics was determined using Vitek 2. Whole-genome sequencing was performed using the Illumina MiSeq platform. Genomes were assembled using Newbler. Phylogenetic analysis was done by determining the core-genome alignments using Panaroo v1.3, analysed in IQ-Tree2 v2.2.0.3 to construct Maximum Likelihood trees using the RaxML software. Resistance genes and IS were identified using the Abricate programme, and ISFinder databases. RESULTS One hundred and thirty-three (n = 133) ST32 A. baumannii isolates were analysed in this study. These genomes originated mainly from US military treatment facilities (n = 113), but also included additional publicly available genomes in GenBank (n = 20) recovered from a broad geographic distribution extending to Asia and South America. Phylogenetic analysis of all 133 genomes revealed at least four clades, with over 80 genomes forming a tightly clustered branch, suggesting they are likely to represent outbreak strains. Analysis of the ampC region showed that ST32 strains played a significant role in the formation of the widely distributed ampC transposon, Tn6168, and supplying DNA segments containing an ISAba1-ampC from ST32s via homologous recombination. CONCLUSIONS ST32 strains played a significant role in the evolution of antibiotic resistance in several widely distributed sequence types including ST1 (global clone 1) and ST3.
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Affiliation(s)
- Liam A Tobin
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Eradah Abu Sabah
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Francois Lebreton
- Multidrug Resistant Organism Repository and Surveillance Network, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Garry S A Myers
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Patrick T McGann
- Multidrug Resistant Organism Repository and Surveillance Network, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Mehrad Hamidian
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, NSW 2007, Australia
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Chen J, Shao Y, Cheng Z, Li G, Wan F, Gao C, Wu D, Wei D, Liu Y, Li R. Exploring the clinical outcomes and molecular characteristics of Acinetobacter baumannii bloodstream infections: a study of sequence types, capsular types, and drug resistance in China. Front Cell Infect Microbiol 2025; 15:1549940. [PMID: 40034394 PMCID: PMC11872892 DOI: 10.3389/fcimb.2025.1549940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2024] [Accepted: 01/28/2025] [Indexed: 03/05/2025] Open
Abstract
Background Bloodstream infections (BSIs) caused by Acinetobacter baumannii have been associated with high mortality. To improve the outcomes of patients, this study explored the clinical characteristics and outcomes of patients with BSIs, as well as the phenotypic and genomic characteristics of these isolates. Methods A retrospective cohort study was conducted involving A. baumannii BSIs cases from 2020 to 2023 in a tertiary hospital. The clinical characteristics of all A. baumannii isolates were evaluated. Virulence phenotypes of all isolates were evaluated using the growth curve, biofilm-forming assay, antiserum complement killing, and G.mellonella killing assay. Furthermore, whole-genome sequencing (WGS) was utilized to analyze genomic characteristics. Results The 30-day mortality rate of 67 patients with BSIs was 55.22%. Patients in the death group had significantly lower platelet counts and higher CRP levels than those in the survival group. Additionally, higher rates of antibiotic use (≥2 classes) and greater carbapenem exposure were observed. Among the isolates, CRAb accounted for 80.6%, ST2 accounted for 76.12%, and KL2/3/7/77/160 accounted for 65.67%. The predominant KL type was KL3, found in 19.4% of the isolates. All ST2 and KL2/3/7/77/160 isolates were CRAb. Among the isolates, 90.7% of the CRAb isolates coharbored blaOXA-23 and blaOXA-66 , while one coharbored blaNDM-1 and blaOXA-23 . Compared with non-ST2 and non KL2/3/7/77/160 infections, ST2 and KL2/3/7/77/160 infections had higher mortality rates (66.0% vs. 23.5%, P=0.002; 65.90% vs. 34.78%, P=0.015). Patients with ST2 and KL2/3/7/77/160 infections underwent more invasive procedures, received two or more antibiotics and carbapenem therapy before isolation, and had lower serum albumin levels. These isolates exhibited significantly higher resistance to antimicrobial agents. No significant differences in virulence phenotypes were observed between the two groups, except for biofilm formation between the ST2 and non-ST2 groups (P=0.002). However, these isolates harbored more virulence genes related to iron uptake and biofilm formation. Conclusion The mortality rate associated with BSIs caused by A. baumannii is high. It is of great significance for clinicians to pay attention to the risk factors of the clinical characteristics of patients and to identify the ST and KL types of the strains causing the infection at an early stage.
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Affiliation(s)
- Jiao Chen
- School of Laboratory Medicine, Nanchang Medical College, Nanchang, China
| | - Yanting Shao
- School of Laboratory Medicine, Nanchang Medical College, Nanchang, China
| | - Zhibin Cheng
- School of Laboratory Medicine, Nanchang Medical College, Nanchang, China
| | - Guanghui Li
- School of Information Engineering, East China Jiaotong University, Nanchang, China
| | - Fen Wan
- School of Laboratory Medicine, Nanchang Medical College, Nanchang, China
| | - Chenyan Gao
- School of Laboratory Medicine, Nanchang Medical College, Nanchang, China
| | - Danqin Wu
- Neurology Intensive Care Unit (ICU), First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Dandan Wei
- Department of Clinical Microbiology, the First Affiliated Hospital of Nanchang University, Nanchang, China
- Clinical Laboratory, China-Japan Friendship Jiang Xi Hospital, Nanchang, China
| | - Yang Liu
- Department of Clinical Microbiology, the First Affiliated Hospital of Nanchang University, Nanchang, China
- Clinical Laboratory, China-Japan Friendship Jiang Xi Hospital, Nanchang, China
| | - Rong Li
- Department of Clinical Laboratory & Jiangxi Province Key Laboratory of Immunology and Inflammation, Jiangxi Provincial People's Hospital & The first Affiliated Hospital of Nanchang Medical College, Nanchang, China
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12
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Din NS, Mohd. Rani F, Alattraqchi AG, Ismail S, A. Rahman NI, Cleary DW, Clarke SC, Yeo CC. Whole-genome sequencing of Acinetobacter baumannii clinical isolates from a tertiary hospital in Terengganu, Malaysia (2011-2020), revealed the predominance of the Global Clone 2 lineage. Microb Genom 2025; 11:001345. [PMID: 39908088 PMCID: PMC11798184 DOI: 10.1099/mgen.0.001345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2024] [Accepted: 12/13/2024] [Indexed: 02/06/2025] Open
Abstract
Carbapenem-resistant Acinetobacter baumannii is recognized by the World Health Organization (WHO) as one of the top priority pathogens. Despite its public health importance, genomic data of clinical isolates from Malaysia remain scarce. In this study, whole-genome sequencing was performed on 126 A. baumannii isolates collected from the main tertiary hospital in the state of Terengganu, Malaysia, over a 10-year period (2011-2020). Antimicrobial susceptibilities determined for 20 antibiotics belonging to 8 classes showed that 77.0% (n=97/126) of the isolates were categorized as multidrug resistant (MDR), with all MDR isolates being carbapenem resistant. Multilocus sequence typing analysis categorized the Terengganu A. baumannii clinical isolates into 34 Pasteur and 44 Oxford sequence types (STs), with ST2Pasteur of the Global Clone 2 lineage identified as the dominant ST (n=76/126; 60.3%). The ST2Pasteur isolates could be subdivided into six Oxford STs with the majority being ST195Oxford (n=35) and ST208Oxford (n=17). Various antimicrobial resistance genes were identified with the bla OXA-23-encoded carbapenemase being the predominant acquired carbapenemase gene (n=90/126; 71.4%). Plasmid-encoded rep genes were identified in nearly all (n=122/126; 96.8%) of the isolates with the majority being Rep_3 family (n=121). Various virulence factors were identified, highlighting the pathogenic nature of this bacterium. Only 14/126 (11.1%) of the isolates were positive for the carriage of CRISPR-Cas arrays with none of the prevalent ST2Pasteur isolates harbouring them. This study provided a genomic snapshot of the A. baumannii isolates obtained from a single tertiary healthcare centre in Malaysia over a 10-year period and showed the predominance of a single closely related ST2Pasteur lineage, indicating the entrenchment of this clone in the hospital.
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Affiliation(s)
- Nurul Saidah Din
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Farahiyah Mohd. Rani
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Ahmed Ghazi Alattraqchi
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Salwani Ismail
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - Nor Iza A. Rahman
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
| | - David W. Cleary
- Department of Microbes, Infections and Microbiomes, School of Infection, Inflammation and Immunology, College of Medicine and Health, University of Birmingham, Birmingham, UK
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Stuart C. Clarke
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- Global Health Research Institute, University of Southampton, Southampton, UK
- Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
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He Z, Huang Y, Li W, Zhang H, Cao R, Ali MR, Dai Y, Lu H, Wang W, Niu Q, Sun B, Li Y. Characterization and genomic analysis of the highly virulent Acinetobacter baumannii ST1791 strain dominating in Anhui, China. Antimicrob Agents Chemother 2025; 69:e0126224. [PMID: 39641569 PMCID: PMC11784083 DOI: 10.1128/aac.01262-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2024] [Accepted: 11/11/2024] [Indexed: 12/07/2024] Open
Abstract
The multidrug-resistant Acinetobacter baumannii clonal complex 92 is spreading worldwide due to its high-frequency gene mutation and recombination, posing a significant threat to global medical and health safety. Between November 2021 and April 2022, a total of 132 clinical A. baumannii isolates were collected from a tertiary hospital in China. Their growth ability and virulence of these isolates were assessed using growth curve analyses and the Galleria mellonella infection model. The genetic characteristics of the isolates were further examined through whole-genome sequencing. ST1791O/ST2P isolates represented the largest proportion of isolates in our collection and exhibited the highest growth rate and strongest virulence among all sequence types (STs) analyzed. Whole-genome sequences from 14,159 clinical isolates were collected from the National Center for Biotechnology Information database, and only nine ST1791O/ST2P isolates were detected. Comparative genomic analysis revealed that ST1791O/ST2P carried 11 unique genes, 5 of which were located within the capsular polysaccharide synthesis (cps) gene cluster. Single nucleotide polymorphisms (SNPs) between ST1791O/ST2P and other isolates were primarily found in the cps gene cluster. Among the other isolates, ST195O/ST2P and ST208O/ST2P exhibited the smallest SNP differences from ST1791O/ST2P, while ST195O/ST2P and ST1486O/ST2P had high homology. The ST1791O/ST2P strain in Anhui, China, displayed significant homology with ST195O/ST2P, ST208O/ST2P, and ST1486O/ST2P isolates. Compared to other isolates in this study, ST1791O/ST2P exhibited strong growth ability and virulence. Therefore, preventing the further spread of ST1791O/ST2P should be a top public health priority.
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Affiliation(s)
- Zhien He
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Yi Huang
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Wei Li
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Huanhuan Zhang
- Department of Cancer Epigenetics Program, The First Affiliated Hospital of University of Science and Technology of China, Hefei, Anhui, China
| | - Ruobing Cao
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Md Roushan Ali
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Yuanyuan Dai
- Department of Clinical Laboratory, the First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Huaiwei Lu
- Department of Clinical Laboratory, the First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Wanying Wang
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Qiuhong Niu
- School of Life Science, Nanyang Normal University, Nanyang, Henan, China
| | - Baolin Sun
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Yujie Li
- Department of Oncology, The First Affiliated Hospital of University of Science and Technology of China, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
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Magda M, Boschloo W, Bettoni S, Fairley D, Russo TA, Giske CG, Tellapragada C, Rooijakkers SH, Riesbeck K, Blom AM. Acinetobacter baumannii Clinical Isolates Resist Complement-Mediated Lysis by Inhibiting the Complement Cascade and Improperly Depositing MAC. J Innate Immun 2025; 17:112-125. [PMID: 39842423 PMCID: PMC11845171 DOI: 10.1159/000543664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2024] [Accepted: 01/15/2025] [Indexed: 01/24/2025] Open
Abstract
INTRODUCTION Acinetobacter baumannii is a gram-negative opportunistic bacterium that causes life-threatening infections in immunocompromised hosts. The complement system is a critical mechanism of innate immunity that protects the human body from bacterial infections. Complement activation leads to the deposition of the membrane attack complex (MAC), which can directly lyse gram-negative bacteria. However, A. baumannii has developed evasion mechanisms to protect itself from complement. METHODS Complement deposition was investigated by flow cytometry and Western blotting. Soluble MAC formation was assessed by ELISA. Bacterial serum resistance was determined by the SYTOX Green Assay. Galleria mellonella was used as an infection model. Genome sequencing revealed virulence genes carried by isolates. RESULTS We examined clinical isolates of A. baumannii and found 11 isolates with MAC deposition and 5 isolates without deposition. Trypsinization of MAC-positive isolates significantly reduced MAC, indicating incorrect insertion, consistent with a lack of lysis of these strains. MAC-negative isolates inhibited alternative pathway activation and were significantly more serum-resistant. These strains were also more virulent in a G. mellonella infection model. Whole genome sequencing revealed that MAC-negative isolates carried more virulence genes, and both MAC-negative and MAC-positive A. baumannii significantly differed in capsule type. Importantly, a correlation was observed between complement inhibition and capsule type (e.g., capsule locus KL171) of MAC-negative bacteria, while the capsule type (e.g., KL230) of MAC-positive A. baumannii was associated with increased sensitivity to MAC-mediated lysis. CONCLUSION Our findings suggest a relationship between capsule type, complement resistance, and host virulence in A. baumannii. INTRODUCTION Acinetobacter baumannii is a gram-negative opportunistic bacterium that causes life-threatening infections in immunocompromised hosts. The complement system is a critical mechanism of innate immunity that protects the human body from bacterial infections. Complement activation leads to the deposition of the membrane attack complex (MAC), which can directly lyse gram-negative bacteria. However, A. baumannii has developed evasion mechanisms to protect itself from complement. METHODS Complement deposition was investigated by flow cytometry and Western blotting. Soluble MAC formation was assessed by ELISA. Bacterial serum resistance was determined by the SYTOX Green Assay. Galleria mellonella was used as an infection model. Genome sequencing revealed virulence genes carried by isolates. RESULTS We examined clinical isolates of A. baumannii and found 11 isolates with MAC deposition and 5 isolates without deposition. Trypsinization of MAC-positive isolates significantly reduced MAC, indicating incorrect insertion, consistent with a lack of lysis of these strains. MAC-negative isolates inhibited alternative pathway activation and were significantly more serum-resistant. These strains were also more virulent in a G. mellonella infection model. Whole genome sequencing revealed that MAC-negative isolates carried more virulence genes, and both MAC-negative and MAC-positive A. baumannii significantly differed in capsule type. Importantly, a correlation was observed between complement inhibition and capsule type (e.g., capsule locus KL171) of MAC-negative bacteria, while the capsule type (e.g., KL230) of MAC-positive A. baumannii was associated with increased sensitivity to MAC-mediated lysis. CONCLUSION Our findings suggest a relationship between capsule type, complement resistance, and host virulence in A. baumannii.
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Affiliation(s)
- Michal Magda
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Wendy Boschloo
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Serena Bettoni
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Derek Fairley
- Department of Microbiology, Belfast Health and Social Care Trust, Belfast, UK
| | - Thomas A. Russo
- Veterans Administration Western New York Healthcare System, Department of Medicine, Jacobs School of Medicine and Biomedical Sciences, University Buffalo, Buffalo, NY, USA
| | | | | | - Suzan H.M. Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Kristian Riesbeck
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Anna M. Blom
- Department of Translational Medicine, Lund University, Malmö, Sweden
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Humberto BC, Luis LA, Josefina DB. Genomic analysis of the main epidemiological lineages of Acinetobacter baumannii in Mexico. Front Cell Infect Microbiol 2025; 14:1499839. [PMID: 39867342 PMCID: PMC11757933 DOI: 10.3389/fcimb.2024.1499839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2024] [Accepted: 12/10/2024] [Indexed: 01/28/2025] Open
Abstract
Acinetobacter baumannii has emerged as a critical global health threat due to its exceptional survival skills in adverse environment and its ability to acquire antibiotic resistance, presenting significant challenges for infection treatment and control. The World Health Organization has classified carbapenem-resistant A. baumannii as a "Critical Priority" pathogen to guide research and the development of control and prevention strategies. Epidemiological surveillance methodologies provide the tools necessary for classifying A. baumannii into international clonal lineages, facilitating the analysis of molecular characteristics, global dissemination, and evolution. This study provides a detailed analysis of the molecular epidemiology of A. baumannii in Mexico, focusing on identifying the main international clonal lineages. Genomic analyses of 146 genomes, along with information from previous studies, identified 24 different sequence types according to the Oxford Scheme. The major international clone IC2 (CC208) was identified and harbors β-lactamases OXA-66, ADC-30, OXA-72, and is predicted to possess the OCL1 locus. The international clone IC5 (CC205) carries β-lactamase OXA-65, along with ADC-214 and OXA-239, with OCL10 predicted in 82.2% of the genomes. The international clone IC7 (CC229) harbors β-lactamase OXA-64, as well as ADC-174 and ADC-214, with OCL6 and OCL7 loci predicted. These international clones were identified in different periods and regions of Mexico and are likely to be widely distributed throughout the country. The analysis of each lineage reveals distinct molecular characteristics, including sequence types, capsule typing, outer core loci, and specific antibiotic resistance profiles. Understanding these features is crucial for elucidating their roles in infection dynamics, resistance mechanisms, and their impact on clinical outcomes.
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Affiliation(s)
- Barrios-Camacho Humberto
- Centro de Investigación Sobre Enfermedades Infecciosas (CISEI), Departamento de Diagnóstico Epidemiológico, Instituto Nacional de Salud Pública (INSP), Cuernavaca, Mexico
| | - Lozano-Aguirre Luis
- Programa de Genómica Evolutiva, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Duran-Bedolla Josefina
- Centro de Investigación Sobre Enfermedades Infecciosas (CISEI), Departamento de Diagnóstico Epidemiológico, Instituto Nacional de Salud Pública (INSP), Cuernavaca, Mexico
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Flaugnatti N, Bader L, Croisier-Coeytaux M, Blokesch M. Capsular polysaccharide restrains type VI secretion in Acinetobacter baumannii. eLife 2025; 14:e101032. [PMID: 39749675 PMCID: PMC11731876 DOI: 10.7554/elife.101032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Accepted: 01/02/2025] [Indexed: 01/04/2025] Open
Abstract
The type VI secretion system (T6SS) is a sophisticated, contact-dependent nanomachine involved in interbacterial competition. To function effectively, the T6SS must penetrate the membranes of both attacker and target bacteria. Structures associated with the cell envelope, like polysaccharides chains, can therefore introduce spatial separation and steric hindrance, potentially affecting the efficacy of the T6SS. In this study, we examined how the capsular polysaccharide (CPS) of Acinetobacter baumannii affects T6SS's antibacterial function. Our findings show that the CPS confers resistance against T6SS-mediated assaults from rival bacteria. Notably, under typical growth conditions, the presence of the surface-bound capsule also reduces the efficacy of the bacterium's own T6SS. This T6SS impairment is further enhanced when CPS is overproduced due to genetic modifications or antibiotic treatment. Furthermore, we demonstrate that the bacterium adjusts the level of the T6SS inner tube protein Hcp according to its secretion capacity, by initiating a degradation process involving the ClpXP protease. Collectively, our findings contribute to a better understanding of the dynamic relationship between T6SS and CPS and how they respond swiftly to environmental challenges.
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Affiliation(s)
- Nicolas Flaugnatti
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Loriane Bader
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Mary Croisier-Coeytaux
- Bioelectron Microscopy Core Facility, School of Life Sciences, Station 19, EPFL-SV-PTBIOEM, Ecole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Melanie Blokesch
- Laboratory of Molecular Microbiology, Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de LausanneLausanneSwitzerland
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Liu H, Moran RA, Doughty EL, Hua X, Snaith AE, Zhang L, Chen X, Guo F, van Schaik W, McNally A, Yu Y. Longitudinal genomics reveals carbapenem-resistant Acinetobacter baumannii population changes with emergence of highly resistant ST164 clone. Nat Commun 2024; 15:9483. [PMID: 39488505 PMCID: PMC11531505 DOI: 10.1038/s41467-024-53817-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2024] [Accepted: 10/23/2024] [Indexed: 11/04/2024] Open
Abstract
Carbapenem-resistant Acinetobacter baumannii (CRAB) is a persistent nosocomial pathogen that poses a significant threat to global public health, particularly in intensive care units (ICUs). Here we report a three-month longitudinal genomic surveillance study conducted in a Hangzhou ICU in 2021. This followed a three-month study conducted in the same ICU in 2019, and infection prevention and control (IPC) interventions targeting patients, staff and the ICU environment. Most A. baumannii isolated in this ICU in 2021 were CRAB (80.9%; 419/518) with higher-level resistance to carbapenems. This was accompanied by the proportion of global clone 2 (GC2) isolates falling from 99.5% in 2019 to 50.8% (213/419) in 2021. The phylogenetic diversity of GC2 increased, apparently driven by regular introductions of distinct clusters in association with patients. The remaining CRAB (40.2%; 206/419) were a highly clonal population of ST164. Isolates of ST164 carried blaNDM-1 and blaOXA-23 carbapenemase genes, and exhibited higher carbapenem MIC50/MIC90 values than GC2. Comparative analysis of publicly available genomes from 26 countries (five continents) revealed that ST164 has evolved towards carbapenem resistance on multiple independent occasions. Its success in this ICU and global capacity for acquiring resistance determinants indicate that ST164 CRAB is an emerging high-risk lineage of global concern.
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Affiliation(s)
- Haiyang Liu
- Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, 158 Shangtang Road, 310014, Hangzhou, Zhejiang, China
- Zhejiang University School of Medicine, Hangzhou, 310016, Hangzhou, Zhejiang, China
| | - Robert A Moran
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Emma L Doughty
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Xiaoting Hua
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310016, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, 310016, Hangzhou, Zhejiang, China
| | - Ann E Snaith
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Linghong Zhang
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310016, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, 310016, Hangzhou, Zhejiang, China
| | - Xiangping Chen
- Intensive Care Unit, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310016, Hangzhou, Zhejiang, China
| | - Feng Guo
- Intensive Care Unit, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310016, Hangzhou, Zhejiang, China
| | - Willem van Schaik
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Alan McNally
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
| | - Yunsong Yu
- Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, 158 Shangtang Road, 310014, Hangzhou, Zhejiang, China.
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310016, Hangzhou, Zhejiang, China.
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18
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Shashkov AS, Arbatsky NP, Senchenkova SN, Kasimova AA, Dmitrenok AS, Shneider MM, Knirel YA, Hall RM, Kenyon JJ. Characterization of the carbapenem-resistant Acinetobacter baumannii clinical reference isolate BAL062 (CC2:KL58:OCL1): resistance properties and capsular polysaccharide structure. mSystems 2024; 9:e0094124. [PMID: 39254035 PMCID: PMC11494974 DOI: 10.1128/msystems.00941-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2024] [Accepted: 08/19/2024] [Indexed: 09/11/2024] Open
Abstract
The carbapenem-resistant Acinetobacter baumannii isolate BAL062 is a clinical reference isolate used in several recent experimental studies. It is from a ventilator-associated pneumonia (VAP) patient in an intensive care unit at the Hospital for Tropical Diseases (HTD), Ho Chi Minh City, Vietnam in 2009. Here, BAL062 was found to belong to the B sub-lineage of global clone 2 (GC2) isolates in the previously reported outbreak (2008 and 2012) of carbapenem-resistant VAP A. baumannii at the HTD. While related sub-lineage B outbreak isolates were extensively antibiotic-resistant and carry GC2-associated genomic resistance islands, AbGRI1, AbGRI2, and AbGRI3, BAL062 has lost AbGRI3 and three aminoglycoside resistance genes, armA, aacA4, and aphA1, leading to amikacin, tobramycin and kanamycin susceptibility. The location of Tn2008VAR found in the chromosome of this sub-lineage was also corrected. Like many of the outbreak isolates, BAL062 carries the KL58 gene cluster at the capsular polysaccharide (CPS) synthesis locus and an annotation key is provided. As information about K type is important for the development of novel CPS-targeting therapies, the BAL062 K58-type CPS structure was established using NMR spectroscopy. It is most closely related to K2 and K93, sharing similar configurations and linkages between K units, and contains the rare higher monosaccharide, 5,7-diacetamido-3,5,7,9-tetradeoxy-d-glycero-l-manno-non-2-ulosonic acid (5,7-di-N-acetyl-8-epipseudaminic acid; 8ePse5Ac7Ac), the 8-epimer of Pse5Ac7Ac (5,7-di-N-acetylpseudaminic acid). Inspection of publicly available A. baumannii genomes revealed a wide distribution of the KL58 locus in geographically diverse isolates belonging to several sequence types that were recovered over two decades from clinical, animal, and environmental sources.IMPORTANCEMany published experimental studies aimed at developing a clearer understanding of the pathogenicity of carbapenem-resistant Acinetobacter baumannii strains currently causing treatment failure due to extensive antibiotic resistance are undertaken using historic, laboratory-adapted isolates. However, it is ideal if not imperative that recent clinical isolates are used in such studies. The clinical reference isolate characterized here belongs to the dominant A. baumannii GC2 clone causing extensively resistant infections and has been used in various recent studies. The correlation of resistance profiles and resistance gene data is key to identifying genes available for gene knockout and complementation analyses, and we have mapped the antibiotic resistance genes to find candidates. Novel therapies, such as bacteriophage or monoclonal antibody therapies, currently under investigation as alternatives or adjuncts to antibiotic treatment to combat difficult-to-treat CRAb infections often exhibit specificity for specific structural epitopes of the capsular polysaccharide (CPS), the outer-most polysaccharide layer. Here, we have solved the structure of the CPS type found in BAL062 and other extensively resistant isolates. As consistent gene naming and annotation are important for locus identification and interpretation of experimental studies, we also have correlated automatic annotations to the standard gene names.
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Affiliation(s)
- Alexander S. Shashkov
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Nikolay P. Arbatsky
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Sof’ya N. Senchenkova
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya A. Kasimova
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Andrei S. Dmitrenok
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail M. Shneider
- M. M. Shemyakin & Y. A Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Yuriy A. Knirel
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Ruth M. Hall
- School of Life and Environmental Science, The University of Sydney, Sydney, Australia
| | - Johanna J. Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
- School of Pharmacy and Medical Sciences, Health Group, Griffith University, Gold Coast, Australia
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19
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Koncz M, Stirling T, Hadj Mehdi H, Méhi O, Eszenyi B, Asbóth A, Apjok G, Tóth Á, Orosz L, Vásárhelyi BM, Ari E, Daruka L, Polgár TF, Schneider G, Zalokh SA, Számel M, Fekete G, Bohár B, Nagy Varga K, Visnyovszki Á, Székely E, Licker MS, Izmendi O, Costache C, Gajic I, Lukovic B, Molnár S, Szőcs-Gazdi UO, Bozai C, Indreas M, Kristóf K, Van der Henst C, Breine A, Pál C, Papp B, Kintses B. Genomic surveillance as a scalable framework for precision phage therapy against antibiotic-resistant pathogens. Cell 2024; 187:5901-5918.e28. [PMID: 39332413 DOI: 10.1016/j.cell.2024.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/15/2024] [Accepted: 09/04/2024] [Indexed: 09/29/2024]
Abstract
Phage therapy is gaining increasing interest in the fight against critically antibiotic-resistant nosocomial pathogens. However, the narrow host range of bacteriophages hampers the development of broadly effective phage therapeutics and demands precision approaches. Here, we combine large-scale phylogeographic analysis with high-throughput phage typing to guide the development of precision phage cocktails targeting carbapenem-resistant Acinetobacter baumannii, a top-priority pathogen. Our analysis reveals that a few strain types dominate infections in each world region, with their geographical distribution remaining stable within 6 years. As we demonstrate in Eastern Europe, this spatiotemporal distribution enables preemptive preparation of region-specific phage collections that target most local infections. Finally, we showcase the efficacy of phage cocktails against prevalent strain types using in vitro and animal infection models. Ultimately, genomic surveillance identifies patients benefiting from the same phages across geographical scales, thus providing a scalable framework for precision phage therapy.
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Affiliation(s)
- Mihály Koncz
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Translational Microbiology Research Group, Budapesti út 9, 6728 Szeged, Hungary
| | - Tamás Stirling
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Translational Microbiology Research Group, Budapesti út 9, 6728 Szeged, Hungary; Doctoral School of Biology, University of Szeged, Dugonics tér 13, 6720 Szeged, Hungary
| | - Hiba Hadj Mehdi
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Translational Microbiology Research Group, Budapesti út 9, 6728 Szeged, Hungary; Doctoral School of Biology, University of Szeged, Dugonics tér 13, 6720 Szeged, Hungary
| | - Orsolya Méhi
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Bálint Eszenyi
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - András Asbóth
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Translational Microbiology Research Group, Budapesti út 9, 6728 Szeged, Hungary; Department of Genetics, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, 1117 Budapest, Hungary
| | - Gábor Apjok
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Ákos Tóth
- National Center for Public Health and Pharmacy, Albert Flórián út 2-6, 1097 Budapest, Hungary
| | - László Orosz
- Department of Medical Microbiology, University of Szeged, Szent-Györgyi Albert Medical School, Dom tér 10, 6720 Szeged, Hungary
| | - Bálint Márk Vásárhelyi
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Eszter Ari
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; Department of Genetics, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/C, 1117 Budapest, Hungary; HCEMM-BRC Metabolic Systems Biology Group, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Lejla Daruka
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Tamás Ferenc Polgár
- Institute of Biophysics, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; Theoretical Medicine Doctoral School, University of Szeged, Dugonics tér 13, 6720 Szeged, Hungary
| | - György Schneider
- Department of Medical Microbiology and Immunology, Medical School, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - Sif Aldin Zalokh
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Mónika Számel
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Gergely Fekete
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Metabolic Systems Biology Group, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Balázs Bohár
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; Faculty of Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, 10th Floor Commonwealth Building Hammersmith Campus, Du Cane Road, London W12 0NN, UK
| | - Karolina Nagy Varga
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Ádám Visnyovszki
- South-Pest Central Hospital National Institute of Hematology and Infectious Diseases, Nagyvárad tér 1, 1097 Budapest, Hungary; Doctoral School of Interdisciplinary Medical Sciences, University of Szeged, Dugonics tér 13, 6720 Szeged, Hungary
| | - Edit Székely
- George Emil Palade University of Medicine, Pharmacy, Science and Technology of Targu Mures, Str. Gheorghe Marinescu 38, 540142 Targu Mures, Romania; County Emergency Clinical Hospital of Targu Mures, Str. Dr. Gh. Marinescu 50, 540136 Targu Mures, Romania
| | - Monica-Sorina Licker
- Microbiology Department, Multidisciplinary Research Center on Antimicrobial Resistance, "Victor Babes" University of Medicine and Pharmacy, Str. Eftimie Murgu 2, 300041 Timisoara, Romania; Microbiology Laboratory, "Pius Branzeu" Emergency Clinical County Hospital, Str. Liviu Rebreanu 156, 300723 Timisoara, Romania
| | - Oana Izmendi
- Microbiology Department, Multidisciplinary Research Center on Antimicrobial Resistance, "Victor Babes" University of Medicine and Pharmacy, Str. Eftimie Murgu 2, 300041 Timisoara, Romania; Microbiology Laboratory, "Pius Branzeu" Emergency Clinical County Hospital, Str. Liviu Rebreanu 156, 300723 Timisoara, Romania; Doctoral School, "Victor Babes" University of Medicine and Pharmacy, Str. Eftimie Murgu 2, 300041 Timisoara, Romania
| | - Carmen Costache
- Department of Microbiology, University of Medicine and Pharmacy "Iuliu Hatieganu" Cluj-Napoca, Str. Victor Babes 8, 400347 Cluj-Napoca, Romania
| | - Ina Gajic
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia
| | - Bojana Lukovic
- Academy of Applied Studies Belgrade, College of Health Sciences, Bulevar Zorana Djindjica 152a, Belgrade, Serbia
| | - Szabolcs Molnár
- Emergency County Hospital Miercurea-Ciuc, Str. Doctor Dénes László 2, 530173 Miercurea Ciuc, Romania
| | | | - Csilla Bozai
- County Emergency Hospital Satu Mare, Str. Ravensburg 1-3, 440192 Satu Mare, Romania
| | - Marina Indreas
- Bacau County Emergency Hospital, Str. Haret Spiru 2-4, 600114 Bacau, Romania
| | - Katalin Kristóf
- Institute of Laboratory Medicine, Semmelweis University, Üllői út 78/b, 1083 Budapest, Hungary
| | - Charles Van der Henst
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Pleinlaan 2, Building E-3, 1050 Brussels, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, Elsene, 1050 Brussels, Belgium
| | - Anke Breine
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Pleinlaan 2, Building E-3, 1050 Brussels, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, Elsene, 1050 Brussels, Belgium
| | - Csaba Pál
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary
| | - Balázs Papp
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Metabolic Systems Biology Group, Temesvári Krt. 62, 6726 Szeged, Hungary; National Laboratory for Health Security, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary.
| | - Bálint Kintses
- Synthetic and Systems Biology Unit, Institute of Biochemistry, National Laboratory of Biotechnology, HUN-REN Biological Research Centre, Temesvári Krt. 62, 6726 Szeged, Hungary; HCEMM-BRC Translational Microbiology Research Group, Budapesti út 9, 6728 Szeged, Hungary.
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20
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Mazzamurro F, Chirakadavil JB, Durieux I, Poiré L, Plantade J, Ginevra C, Jarraud S, Wilharm G, Charpentier X, P. C. Rocha E. Intragenomic conflicts with plasmids and chromosomal mobile genetic elements drive the evolution of natural transformation within species. PLoS Biol 2024; 22:e3002814. [PMID: 39401218 PMCID: PMC11472951 DOI: 10.1371/journal.pbio.3002814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 08/27/2024] [Indexed: 10/17/2024] Open
Abstract
Natural transformation is the only mechanism of genetic exchange controlled by the recipient bacteria. We quantified its rates in 786 clinical strains of the human pathogens Legionella pneumophila (Lp) and 496 clinical and environmental strains of Acinetobacter baumannii (Ab). The analysis of transformation rates in the light of phylogeny revealed they evolve by a mixture of frequent small changes and a few large quick jumps across 6 orders of magnitude. In standard conditions close to half of the strains of Lp and a more than a third in Ab are below the detection limit and thus presumably non-transformable. Ab environmental strains tend to have higher transformation rates than the clinical ones. Transitions to non-transformability were frequent and usually recent, suggesting that they are deleterious and subsequently purged by natural selection. Accordingly, we find that transformation decreases genetic linkage in both species, which might accelerate adaptation. Intragenomic conflicts with chromosomal mobile genetic elements (MGEs) and plasmids could explain these transitions and a GWAS confirmed systematic negative associations between transformation and MGEs: plasmids and other conjugative elements in Lp, prophages in Ab, and transposable elements in both. In accordance with the hypothesis of modulation of transformation rates by genetic conflicts, transformable strains have fewer MGEs in both species and some MGEs inactivate genes implicated in the transformation with heterologous DNA (in Ab). Innate defense systems against MGEs are associated with lower transformation rates, especially restriction-modification systems. In contrast, CRISPR-Cas systems are associated with higher transformation rates suggesting that adaptive defense systems may facilitate cell protection from MGEs while preserving genetic exchanges by natural transformation. Ab and Lp have different lifestyles, gene repertoires, and population structure. Nevertheless, they exhibit similar trends in terms of variation of transformation rates and its determinants, suggesting that genetic conflicts could drive the evolution of natural transformation in many bacteria.
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Affiliation(s)
- Fanny Mazzamurro
- Institut Pasteur, Université Paris Cité, CNRS UMR3525, Microbial Evolutionary Genomics, Paris, France
- Collège Doctoral–Sorbonne Université, Paris, France
| | - Jason Baby Chirakadavil
- CIRI, Centre International de Recherche en Infectiologie–Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Villeurbanne, France
| | - Isabelle Durieux
- CIRI, Centre International de Recherche en Infectiologie–Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Villeurbanne, France
| | - Ludovic Poiré
- CIRI, Centre International de Recherche en Infectiologie–Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Villeurbanne, France
| | - Julie Plantade
- CIRI, Centre International de Recherche en Infectiologie–Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Villeurbanne, France
| | - Christophe Ginevra
- Centre national de Référence des Légionelles–Centre de biologie Nord, Lyon, Cedex 04, France
| | - Sophie Jarraud
- Centre national de Référence des Légionelles–Centre de biologie Nord, Lyon, Cedex 04, France
| | - Gottfried Wilharm
- Robert Koch Institute, Project group P2, Wernigerode Branch, Wernigerode, Germany
| | - Xavier Charpentier
- CIRI, Centre International de Recherche en Infectiologie–Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Univ Lyon, Villeurbanne, France
| | - Eduardo P. C. Rocha
- Institut Pasteur, Université Paris Cité, CNRS UMR3525, Microbial Evolutionary Genomics, Paris, France
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21
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Baker S, Krishna A, Higham S, Naydenova P, O'Leary S, Scott JB, Harcourt K, Forrest S, Goulding D, Thi Nguyen TN, Toan ND, Alekseeva E, Zhou Q, Andreozzi I, Sobotic B, Craig H, Wong V, Forrest-Owen N, Sanchez DM, Pearce C, Roberts L, Watson S, Clare S, Torok ME, Dougan G, Kellam P, Tregoning JS, Reece ST. Exploiting human immune repertoire transgenic mice for protective monoclonal antibodies against antimicrobial resistant Acinetobacter baumannii. Nat Commun 2024; 15:7979. [PMID: 39266557 PMCID: PMC11392949 DOI: 10.1038/s41467-024-52357-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 09/04/2024] [Indexed: 09/14/2024] Open
Abstract
The use of monoclonal antibodies for the control of drug resistant nosocomial bacteria may alleviate a reliance on broad spectrum antimicrobials for treatment of infection. We identify monoclonal antibodies that may prevent infection caused by carbapenem resistant Acinetobacter baumannii. We use human immune repertoire mice (Kymouse platform mice) as a surrogate for human B cell interrogation to establish an unbiased strategy to probe the antibody-accessible target landscape of clinically relevant A. baumannii. After immunisation of the Kymouse platform mice with A. baumannii derived outer membrane vesicles (OMV) we identify 297 antibodies and analyse 26 of these for functional potential. These antibodies target lipooligosaccharide (OCL1), the Oxa-23 protein, and the KL49 capsular polysaccharide. We identify a single monoclonal antibody (mAb1416) recognising KL49 capsular polysaccharide to demonstrate prophylactic in vivo protection against a carbapenem resistant A. baumannii lineage associated with neonatal sepsis mortality in Asia. Our end-to-end approach identifies functional monoclonal antibodies with prophylactic potential against major lineages of drug resistant bacteria accounting for phylogenetic diversity and clinical relevance without existing knowledge of a specific target antigen. Such an approach might be scaled for a additional clinically important bacterial pathogens in the post-antimicrobial era.
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Affiliation(s)
- Stephen Baker
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
- IAVI, Chelsea and Westminster Hospital, London, UK
| | | | - Sophie Higham
- Department of Infectious Disease, Imperial College London, St Marys Campus, Norfolk Place, London, UK
| | - Plamena Naydenova
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
| | - Siobhan O'Leary
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | | | - Katherine Harcourt
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
| | - Sally Forrest
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
| | - David Goulding
- Pathogens and Microbes Programme, Wellcome Sanger Institute, Cambridge, UK
| | - To Nguyen Thi Nguyen
- Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Nguyen Duc Toan
- Neonatal Intensive Care Unit, Children's Hospital 1, Ho Chi Minh City, Vietnam
| | | | - Qingqing Zhou
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | - Ilaria Andreozzi
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | - Barbara Sobotic
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | - Hannah Craig
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | - Vivian Wong
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | | | | | - Claire Pearce
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | - Leah Roberts
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Hinxton, UK
| | - Simon Watson
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
| | - Simon Clare
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
| | - Mili Estee Torok
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
| | - Gordon Dougan
- University of Cambridge School of Clinical Medicine Cambridge Biomedical Campus, Cambridge, UK
| | - Paul Kellam
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK
- Department of Infectious Disease, Imperial College London, St Marys Campus, Norfolk Place, London, UK
| | - John S Tregoning
- Department of Infectious Disease, Imperial College London, St Marys Campus, Norfolk Place, London, UK
| | - Stephen T Reece
- Kymab, a Sanofi Company, Babraham Research Campus, Cambridge, UK.
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Cooper C, Legood S, Wheat RL, Forrest D, Sharma P, Haycocks JRJ, Grainger DC. H-NS is a bacterial transposon capture protein. Nat Commun 2024; 15:7137. [PMID: 39164300 PMCID: PMC11335895 DOI: 10.1038/s41467-024-51407-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 08/05/2024] [Indexed: 08/22/2024] Open
Abstract
The histone-like nucleoid structuring (H-NS) protein is a DNA binding factor, found in gammaproteobacteria, with functional equivalents in diverse microbes. Universally, such proteins are understood to silence transcription of horizontally acquired genes. Here, we identify transposon capture as a major overlooked function of H-NS. Using genome-scale approaches, we show that H-NS bound regions are transposition "hotspots". Since H-NS often interacts with pathogenicity islands, such targeting creates clinically relevant phenotypic diversity. For example, in Acinetobacter baumannii, we identify altered motility, biofilm formation, and interactions with the human immune system. Transposon capture is mediated by the DNA bridging activity of H-NS and, if absent, more ubiquitous transposition results. Consequently, transcribed and essential genes are disrupted. Hence, H-NS directs transposition to favour evolutionary outcomes useful for the host cell.
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Affiliation(s)
- Charles Cooper
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Simon Legood
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Rachel L Wheat
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - David Forrest
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Prateek Sharma
- School of Biosciences, University of Birmingham, Birmingham, UK
| | | | - David C Grainger
- School of Biosciences, University of Birmingham, Birmingham, UK.
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Wang R, Liu Y, Zhang Y, Yu S, Zhuo H, Huang Y, Lyu J, Lin Y, Zhang X, Mi Z, Liu Y. Identification and characterization of the capsule depolymerase Dpo27 from phage IME-Ap7 specific to Acinetobacter pittii. Front Cell Infect Microbiol 2024; 14:1373052. [PMID: 38808067 PMCID: PMC11130378 DOI: 10.3389/fcimb.2024.1373052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 04/11/2024] [Indexed: 05/30/2024] Open
Abstract
Among the Acinetobacter genus, Acinetobacter pittii stands out as an important opportunistic infection causative agent commonly found in hospital settings, which poses a serious threat to human health. Recently, the high prevalence of carbapenem-resistant A. pittii isolates has created significant therapeutic challenges for clinicians. Bacteriophages and their derived enzymes are promising therapeutic alternatives or adjuncts to antibiotics effective against multidrug-resistant bacterial infections. However, studies investigating the depolymerases specific to A. pittii strains are scarce. In this study, we identified and characterized a capsule depolymerase, Dpo27, encoded by the bacteriophage IME-Ap7, which targets A. pittii. A total of 23 clinical isolates of Acinetobacter spp. were identified as A. pittii (21.91%, 23/105), and seven A. pittii strains with various K locus (KL) types (KL14, KL32, KL38, KL111, KL163, KL207, and KL220) were used as host bacteria for phage screening. The lytic phage IME-Ap7 was isolated using A. pittii 7 (KL220) as an indicator bacterium and was observed for depolymerase activity. A putative tail fiber gene encoding a polysaccharide-degrading enzyme (Dpo27) was identified and expressed. The results of the modified single-spot assay showed that both A. pittii 7 and 1492 were sensitive to Dpo27, which was assigned the KL220 type. After incubation with Dpo27, A. pittii strain was susceptible to killing by human serum; moreover, the protein displayed no hemolytic activity against erythrocytes. Furthermore, the protein exhibited sustained activity across a wide pH range (5.0-10.0) and at temperatures between 20 and 50°C. In summary, the identified capsule depolymerase Dpo27 holds promise as an alternative treatment for combating KL220-type A. pittii infections.
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Affiliation(s)
- Rentao Wang
- Senior Department of Respiratory and Critical Care Medicine, the Eighth Medical Center of Chinese PLA General Hospital, Beijing, China
| | - Yannan Liu
- Emergency Medicine Clinical Research Center, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Yaqian Zhang
- School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Shijun Yu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Hailong Zhuo
- Department of Transfusion Medicine, The Fifth Medical Centre of Chinese PLA General Hospital, Beijing, China
| | - Yong Huang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Jinhui Lyu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yu Lin
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Xianglilan Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Zhiqiang Mi
- School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Youning Liu
- Senior Department of Respiratory and Critical Care Medicine, the Eighth Medical Center of Chinese PLA General Hospital, Beijing, China
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Manley R, Fitch C, Francis V, Temperton I, Turner D, Fletcher J, Phil M, Michell S, Temperton B. Resistance to bacteriophage incurs a cost to virulence in drug-resistant Acinetobacter baumannii. J Med Microbiol 2024; 73:001829. [PMID: 38743467 PMCID: PMC11170128 DOI: 10.1099/jmm.0.001829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 04/10/2024] [Indexed: 05/16/2024] Open
Abstract
Introduction . Acinetobacter baumannii is a critical priority pathogen for novel antimicrobials (World Health Organization) because of the rise in nosocomial infections and its ability to evolve resistance to last resort antibiotics. A. baumannii is thus a priority target for phage therapeutics. Two strains of a novel, virulent bacteriophage (LemonAid and Tonic) able to infect carbapenem-resistant A. baumannii (strain NCTC 13420), were isolated from environmental water samples collected through a citizen science programme.Gap statement. Phage-host coevolution can lead to emergence of host resistance, with a concomitant reduction in the virulence of host bacteria; a potential benefit to phage therapy applications.Methodology. In vitro and in vivo assays, genomics and microscopy techniques were used to characterize the phages; determine mechanisms and impact of phage resistance on host virulence, and the efficacy of the phages against A. baumannii.Results. A. baumannii developed resistance to both viruses, LemonAid and Tonic. Resistance came at a cost to virulence, with the resistant variants causing significantly reduced mortality in a Galleria mellonella larval in vivo model. A replicated 8 bp insertion increased in frequency (~40 % higher frequency than in the wild-type) within phage-resistant A. baumannii mutants, putatively resulting in early truncation of a protein of unknown function. Evidence from comparative genomics and an adsorption assay suggests this protein acts as a novel phage receptor site in A. baumannii. We find no evidence linking resistance to changes in capsule structure, a known virulence factor. LemonAid efficiently suppressed growth of A. baumanni in vitro across a wide range of titres. However, in vivo, while survival of A. baumannii infected larvae significantly increased with both remedial and prophylactic treatment with LemonAid (107 p.f.u. ml-1), the effect was weak and not sufficient to save larvae from morbidity and mortality.Conclusion. While LemonAid and Tonic did not prove effective as a treatment in a Galleria larvae model, there is potential to harness their ability to attenuate virulence in drug-resistant A. baumannii.
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Affiliation(s)
- Robyn Manley
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
| | - Christian Fitch
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
| | - Vanessa Francis
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
| | - Isaac Temperton
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
| | - Dann Turner
- School of Applied Sciences, College of Health, Science and Society, University of the West of England, Bristol, Frenchay Campus, Coldharbour Lane, Bristol, BS16 1QY, UK
| | - Julie Fletcher
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
| | - Mitchelmore Phil
- University of Exeter, College of Medicine and Health, Department of Respiratory Medicine, Royal Devon & Exeter Hospital, Barrack Road, Exeter, EX2 5DW, UK
| | - Steve Michell
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
| | - Ben Temperton
- University of Exeter, Health and Life Sciences, Streatham Campus, Exeter, EX4 4QD, UK
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Sykes EME, Mateo-Estrada V, Engelberg R, Muzaleva A, Zhanel G, Dettman J, Chapados J, Gerdis S, Akineden Ö, Khan IUH, Castillo-Ramírez S, Kumar A. Phylogenomic and phenotypic analyses highlight the diversity of antibiotic resistance and virulence in both human and non-human Acinetobacter baumannii. mSphere 2024; 9:e0074123. [PMID: 38440986 PMCID: PMC10964423 DOI: 10.1128/msphere.00741-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/15/2024] [Indexed: 03/06/2024] Open
Abstract
Acinetobacter baumannii is a Gram-negative, opportunistic pathogen that causes infections in the immunocompromised. With a high incidence of muti-drug resistance, carbapenem-resistant A. baumannii is designated as a priority 1 pathogen by the WHO. The current literature has expertly characterized clinical isolates of A. baumannii. As the challenge of these infections has recently been classified as a One Health issue, we set out to explore the diversity of isolates from human and non-clinical sources, such as agricultural surface water, urban streams, various effluents from wastewater treatment plants, and food (tank milk); and, importantly, these isolates came from a wide geographic distribution. Phylogenomic analysis considering almost 200 isolates showed that our diverse set is well-differentiated from the main international clones of A. baumannii. We discovered novel sequence types in both hospital and non-clinical settings and five strains that overexpress the resistance-nodulation-division efflux pump adeIJK without changes in susceptibility reflected by this overexpression. Furthermore, we detected a bla ADC-79 in a non-human isolate despite its sensitivity to all antibiotics. There was no significant differentiation between the virulence profiles of clinical and non-clinical isolates in the Galleria mellonella insect model of virulence, suggesting that virulence is neither dependent on geographic origin nor isolation source. The detection of antibiotic resistance and virulence genes in non-human strains suggests that these isolates may act as a genetic reservoir for clinical strains. This endorses the notion that in order to combat multi-drug-resistant infection caused by A. baumannii, a One Health approach is required, and a deeper understanding of non-clinical strains must be achieved.IMPORTANCEThe global crisis of antibiotic resistance is a silent one. More and more bacteria are becoming resistant to all antibiotics available for treatment, leaving no options remaining. This includes Acinetobacter baumannii. This Gram-negative, opportunistic pathogen shows a high frequency of multi-drug resistance, and many strains are resistant to the last-resort drugs carbapenem and colistin. Research has focused on strains of clinical origin, but there is a knowledge gap regarding virulence traits, particularly how A. baumannii became the notorious pathogen of today. Antibiotic resistance and virulence genes have been detected in strains from animals and environmental locations such as grass and soil. As such, A. baumannii is a One Health concern, which includes the health of humans, animals, and the environment. Thus, in order to truly combat the antibiotic resistance crisis, we need to understand the antibiotic resistance and virulence gene reservoirs of this pathogen under the One Health continuum.
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Affiliation(s)
- Ellen M. E. Sykes
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Valeria Mateo-Estrada
- Programa de Genómica Evolutiva, Centro de Ciencias Génomicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Raelene Engelberg
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Anna Muzaleva
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - George Zhanel
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Jeremy Dettman
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada
| | - Julie Chapados
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada
| | - Suzanne Gerdis
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada
| | - Ömer Akineden
- Dairy Sciences, Institute of Veterinary Food Science, Justus-Liebig, University of Giessen, Giessen, Germany
| | - Izhar U. H. Khan
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada
| | - Santiago Castillo-Ramírez
- Programa de Genómica Evolutiva, Centro de Ciencias Génomicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Ayush Kumar
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
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26
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Zheng C, Li D, Wang Y, Wang L, Huang Y, Yao J. Risk factors and genetic characteristics of the carriage of hypervirulent and carbapenem-resistant Acinetobacter baumannii among pregnant women. Front Microbiol 2024; 15:1351722. [PMID: 38572236 PMCID: PMC10987950 DOI: 10.3389/fmicb.2024.1351722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 02/16/2024] [Indexed: 04/05/2024] Open
Abstract
Background Carbapenem-resistant Acinetobacter baumannii (CRAB) and its emerging evolutionary branch toward hypervirulence have been neglected in pregnancy. Methods From September 2020 to August 2021, an active surveillance culture program encompassed 138 randomly selected pregnant women, with five subjected to sample collection at two different time points. The clinical characterization was explored through statistical analysis. Whole-genome sequencing, a Galleria mellonella infection model, and a global database were used to investigate the genetic characterization, pathogenicity, evolutionary history, and phylogenetic relationships of the isolates. Results Of the 41 CRAB isolates obtained, they were divided into four ClustersRS and an orphan pattern. ClusterRS 1 (n = 31), with eight complex types in pregnancy, was also the dominant ClusterRS globally, followed by ClusterRS 13 (n = 5), identified as hypervirulent KL49 CRAB, exhibiting phylogeographical specificity to Guangdong. A maternal carriage CRAB rate of 26.09% (36/138) was revealed, with half of the isolates representing novel complex types, prominently including CT3071, as the first KL7 isolates identified in Shenzhen. Both KL49 and KL7 isolates were most commonly found in the same participant, suggesting potential intraspecific competition as a possible reason for CRAB infection without carriers during pregnancy. The independent risk factors for carriers were revealed for the first time, including advanced maternal age, gestational diabetes mellitus, and Group B Streptococcus infection. Conclusion The significant carriage rate and enhanced virulence of CRAB during pregnancy emphasize the imperative for routine surveillance to forestall dissemination within this high-risk group, especially in Guangdong for ClusterRS 13 isolates.
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Affiliation(s)
- Chao Zheng
- Department of Gastroenterology, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
- Bacteriology and Antibacterial Resistance Surveillance Laboratory, Shenzhen Institute of Respiratory Disease, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
- Integrated Chinese and Western Medicine Postdoctoral Research Station, Jinan University, Guangzhou, China
- School of Materials and Environmental Engineering, Shenzhen Polytechnic University, Shenzhen, China
| | - Defeng Li
- Department of Gastroenterology, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
| | - Yinglan Wang
- Department of Obstetrics and Gynecology, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
| | - Lisheng Wang
- Department of Gastroenterology, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
| | - Yuting Huang
- Bacteriology and Antibacterial Resistance Surveillance Laboratory, Shenzhen Institute of Respiratory Disease, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
- Department of Head and Neck Surgery, Cancer Hospital Chinese Academy of Medical Sciences Shenzhen Center, Shenzhen, China
| | - Jun Yao
- Department of Gastroenterology, Shenzhen People’s Hospital (The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology), Shenzhen, China
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Gao S, Jin W, Quan Y, Li Y, Shen Y, Yuan S, Yi L, Wang Y, Wang Y. Bacterial capsules: Occurrence, mechanism, and function. NPJ Biofilms Microbiomes 2024; 10:21. [PMID: 38480745 PMCID: PMC10937973 DOI: 10.1038/s41522-024-00497-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 03/05/2024] [Indexed: 03/17/2024] Open
Abstract
In environments characterized by extended multi-stress conditions, pathogens develop a variety of immune escape mechanisms to enhance their ability to infect the host. The capsules, polymers that bacteria secrete near their cell wall, participates in numerous bacterial life processes and plays a crucial role in resisting host immune attacks and adapting to their niche. Here, we discuss the relationship between capsules and bacterial virulence, summarizing the molecular mechanisms of capsular regulation and pathogenesis to provide new insights into the research on the pathogenesis of pathogenic bacteria.
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Affiliation(s)
- Shuji Gao
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Wenjie Jin
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yingying Quan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yue Li
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Yamin Shen
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Shuo Yuan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
| | - Li Yi
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China
- College of Life Science, Luoyang Normal University, Luoyang, 471934, China
| | - Yuxin Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China.
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, 471000, China.
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang, 471003, China.
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28
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Tobin LA, Jarocki VM, Kenyon J, Drigo B, Donner E, Djordjevic SP, Hamidian M. Genomic analysis of diverse environmental Acinetobacter isolates identifies plasmids, antibiotic resistance genes, and capsular polysaccharides shared with clinical strains. Appl Environ Microbiol 2024; 90:e0165423. [PMID: 38206028 PMCID: PMC10885009 DOI: 10.1128/aem.01654-23] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 11/30/2023] [Indexed: 01/12/2024] Open
Abstract
Acinetobacter baumannii, an important pathogen known for its widespread antibiotic resistance, has been the focus of extensive research within its genus, primarily involving clinical isolates. Consequently, data on environmental A. baumannii and other Acinetobacter species remain limited. Here, we utilized Illumina and Nanopore sequencing to analyze the genomes of 10 Acinetobacter isolates representing 6 different species sourced from aquatic environments in South Australia. All 10 isolates were phylogenetically distinct compared to clinical and other non-clinical Acinetobacter strains, often tens of thousands of single-nucleotide polymorphisms from their nearest neighbors. Despite the genetic divergence, we identified pdif modules (sections of mobilized DNA) carrying clinically important antimicrobial resistance genes in species other than A. baumannii, including carbapenemase oxa58, tetracycline resistance gene tet(39), and macrolide resistance genes msr(E)-mph(E). These pdif modules were located on plasmids with high sequence identity to those circulating in globally distributed A. baumannii ST1 and ST2 clones. The environmental A. baumannii isolate characterized here (SAAb472; ST350) did not possess any native plasmids; however, it could capture two clinically important plasmids (pRAY and pACICU2) with high transfer frequencies. Furthermore, A. baumannii SAAb472 possessed virulence genes and a capsular polysaccharide type analogous to clinical strains. Our findings highlight the potential for environmental Acinetobacter species to acquire and disseminate clinically important antimicrobial resistance genes, underscoring the need for further research into the ecology and evolution of this important genus.IMPORTANCEAntimicrobial resistance (AMR) is a global threat to human, animal, and environmental health. Studying AMR in environmental bacteria is crucial to understand the emergence and dissemination of resistance genes and pathogens, and to identify potential reservoirs and transmission routes. This study provides novel insights into the genomic diversity and AMR potential of environmental Acinetobacter species. By comparing the genomes of aquatic Acinetobacter isolates with clinical and non-clinical strains, we revealed that they are highly divergent yet carry pdif modules that encode resistance to antibiotics commonly used in clinical settings. We also demonstrated that an environmental A. baumannii isolate can acquire clinically relevant plasmids and carries virulence factors similar to those of hospital-associated strains. These findings suggest that environmental Acinetobacter species may serve as reservoirs and vectors of clinically important genes. Consequently, further research is warranted to comprehensively understand the ecology and evolution of this genus.
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Affiliation(s)
- Liam A. Tobin
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
| | - Veronica M. Jarocki
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
- The Australian Centre for Genomic Epidemiological Microbiology, University of Technology Sydney, Ultimo, Australia
| | - Johanna Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Barbara Drigo
- Future Industries Institute, University of South Australia, Mawson Lakes, SA, Australia
- UniSA STEM, University of South Australia, Mawson Lakes, SA, Australia
| | - Erica Donner
- Future Industries Institute, University of South Australia, Mawson Lakes, SA, Australia
- Cooperative Research Centre for Solving Antimicrobial Resistance in Agribusiness, Food, and Environments (CRC SAAFE), Adelaide, SA, Australia
| | - Steven P. Djordjevic
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
- The Australian Centre for Genomic Epidemiological Microbiology, University of Technology Sydney, Ultimo, Australia
| | - Mehrad Hamidian
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
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29
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Hamed SM, Mohamed HO, Ashour HM, Fahmy LI. Comparative genomic analysis of strong biofilm-forming Klebsiella pneumoniae isolates uncovers novel IS Ecp1-mediated chromosomal integration of a full plasmid-like sequence. Infect Dis (Lond) 2024; 56:91-109. [PMID: 37897710 DOI: 10.1080/23744235.2023.2272624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 10/12/2023] [Indexed: 10/30/2023] Open
Abstract
BACKGROUND The goal of the current study was to elucidate the genomic background of biofilm formation in Klebsiella pneumoniae. METHODS Clinical isolates were screened for biofilm formation using the crystal violet assay. Antimicrobial resistance (AMR) profiles were assessed by disk diffusion and broth microdilution tests. Biofilm formation was correlated to virulence and resistance genes screened by PCR. Draft genomes of three isolates that form strong biofilm were generated by Illumina sequencing. RESULTS Only the siderophore-coding gene iutA was significantly associated with more pronounced biofilm formation. ST1399-KL43-O1/O2v1 and ST11-KL15-O4 were assigned to the multidrug-resistant strain K21 and the extensively drug-resistant strain K237, respectively. ST1999-KL38-O12 was assigned to K57. Correlated with CRISPR/Cas distribution, more plasmid replicons and prophage sequences were identified in K21 and K237 compared to K57. The acquired AMR genes (blaOXA-48, rmtF, aac(6')-Ib and qnrB) and (blaNDM-1, blaCTX-M, aph(3')-VI, qnrS, and aac(6')-Ib-cr) were found in K237 and K21, respectively. The latter showed a novel ISEcp1-mediated chromosomal integration of replicon type IncM1 plasmid-like structure harboring blaCTX-M-14 and aph(3')-VI that uniquely interrupted rcsC. The plasmid-mediated heavy metal resistance genes merACDEPRT and arsABCDR were spotted in K21, which also exclusively carried the acquired virulence genes mrkABCDF and the hypervirulence-associated genes iucABCD-iutA, and rmpA/A2. Pangenome analysis revealed NTUH-K2044 accessory genes most frequently shared with K21. CONCLUSIONS While less virulent to Galleria mellonella than ST1999 (K57), the strong biofilm former, multidrug-resistant, NDM-producer K. pneumoniae K21 (ST1399-KL43-O1/O2v1) carries a novel chromosomally integrated plasmid-like structure and hypervirulence-associated genes and represents a serious threat to countries in the area.
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Affiliation(s)
- Samira M Hamed
- Department of Microbiology and Immunology, Faculty of Pharmacy, October University for Modern Sciences and Arts (MSA), Giza, Egypt
| | - Hend O Mohamed
- Department of Biological Control Research, Plant Protection Research Institute, Agricultural Research Center, Giza, Egypt
| | - Hossam M Ashour
- Department of Integrative Biology, College of Arts and Sciences, University of South Florida, St. Petersburg, FL, USA
| | - Lamiaa I Fahmy
- Department of Microbiology and Immunology, Faculty of Pharmacy, October University for Modern Sciences and Arts (MSA), Giza, Egypt
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30
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Yang Z, Yang X, Wang M, Jia R, Chen S, Liu M, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Ou X, Mao S, Gao Q, Sun D, Tian B, Zhu D, Cheng A. Genome-wide association study reveals serovar-associated genetic loci in Riemerella anatipestifer. BMC Genomics 2024; 25:57. [PMID: 38216873 PMCID: PMC10787497 DOI: 10.1186/s12864-024-09988-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 01/08/2024] [Indexed: 01/14/2024] Open
Abstract
BACKGROUND The disease caused by Riemerella anatipestifer (R. anatipestifer, RA) results in large economic losses to the global duck industry every year. Serovar-related genomic variation, such as the O-antigen and capsular polysaccharide (CPS) gene clusters, has been widely used for serotyping in many gram-negative bacteria. RA has been classified into at least 21 serovars based on slide agglutination, but the molecular basis of serotyping is unknown. In this study, we performed a pan-genome-wide association study (Pan-GWAS) to identify the genetic loci associated with RA serovars. RESULTS The results revealed a significant association between the putative CPS synthesis gene locus and the serological phenotype. Further characterization of the CPS gene clusters in 11 representative serovar strains indicated that they were highly diverse and serovar-specific. The CPS gene cluster contained the key genes wzx and wzy, which are involved in the Wzx/Wzy-dependent pathway of CPS synthesis. Similar CPS loci have been found in some other species within the family Weeksellaceae. We have also shown that deletion of the wzy gene in RA results in capsular defects and cross-agglutination. CONCLUSIONS This study indicates that the CPS synthesis gene cluster of R. anatipestifer is a serotype-specific genetic locus. Importantly, our finding provides a new perspective for the systematic analysis of the genetic basis of the R anatipestifer serovars and a potential target for establishing a complete molecular serotyping scheme.
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Affiliation(s)
- Zhishuang Yang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
| | - Xueqin Yang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Mingshu Wang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Renyong Jia
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Shun Chen
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Mafeng Liu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Xinxin Zhao
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Qiao Yang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Ying Wu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Shaqiu Zhang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Juan Huang
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Xumin Ou
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Sai Mao
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Qun Gao
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Di Sun
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Bin Tian
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China
| | - Dekang Zhu
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China.
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China.
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China.
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China.
| | - Anchun Cheng
- Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China.
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, Sichuan, China.
- International Joint Research Center for Animal Disease Prevention and Control of Sichuan Province, Chengdu, Sichuan, China.
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, Sichuan, China.
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Müller C, Reuter S, Wille J, Xanthopoulou K, Stefanik D, Grundmann H, Higgins PG, Seifert H. A global view on carbapenem-resistant Acinetobacter baumannii. mBio 2023; 14:e0226023. [PMID: 37882512 PMCID: PMC10746149 DOI: 10.1128/mbio.02260-23] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 09/12/2023] [Indexed: 10/27/2023] Open
Abstract
IMPORTANCE Carbapenem-resistant Acinetobacter baumannii are of increasing public health importance, as they are resistant to last-line antibiotics. International clones with well-characterized resistance genes dominate globally; however, locally, other lineages with different properties may be of importance to consider. This study investigated isolates from a broad geographic origin from 114 hospitals in 47 countries and from five world regions ensuring the greatest possible diversity in an organism known for its propensity for clonal epidemic spread and reflecting the current global epidemiology of carbapenem-resistant A. baumannii. In Latin America, a lineage different from other geographic regions circulates, with a different resistance gene profile. This knowledge is important to adjust local infection prevention measures. In a global world with migration and increasing use of antimicrobials, multidrug-resistant bacteria will continue to adapt and challenge our healthcare systems worldwide.
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Affiliation(s)
- Carina Müller
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, Goldenfelsstr, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany
| | - Sandra Reuter
- Institute for Infection Prevention and Hospital Epidemiology, Medical Centre–University of Freiburg, Freiburg, Germany
| | - Julia Wille
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, Goldenfelsstr, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany
| | - Kyriaki Xanthopoulou
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, Goldenfelsstr, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany
| | - Danuta Stefanik
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, Goldenfelsstr, Cologne, Germany
| | - Hajo Grundmann
- Institute for Infection Prevention and Hospital Epidemiology, Medical Centre–University of Freiburg, Freiburg, Germany
| | - Paul G. Higgins
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, Goldenfelsstr, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany
| | - Harald Seifert
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital Cologne, University of Cologne, Goldenfelsstr, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany
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Kasimova AA, Sharar NS, Ambrose SJ, Knirel YA, Shneider MM, Timoshina OY, Popova AV, Perepelov AV, Dmitrenok AS, Hsu LY, Hall RM, Kenyon JJ. The Acinetobacter baumannii K70 and K9 capsular polysaccharides consist of related K-units linked by the same Wzy polymerase and cleaved by the same phage depolymerases. Microbiol Spectr 2023; 11:e0302523. [PMID: 37975684 PMCID: PMC10715181 DOI: 10.1128/spectrum.03025-23] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 10/12/2023] [Indexed: 11/19/2023] Open
Abstract
IMPORTANCE Bacteriophage show promise for the treatment of Acinetobacter baumannii infections that resist all therapeutically suitable antibiotics. Many tail-spike depolymerases encoded by phage that are able to degrade A. baumannii capsular polysaccharide (CPS) exhibit specificity for the linkage present between K-units that make up CPS polymers. This linkage is formed by a specific Wzy polymerase, and the ability to predict this linkage using sequence-based methods that identify the Wzy at the K locus could assist with the selection of phage for therapy. However, little is known about the specificity of Wzy polymerase enzymes. Here, we describe a Wzy polymerase that can accommodate two different but similar sugars as one of the residues it links and phage depolymerases that can cleave both types of bond that Wzy forms.
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Affiliation(s)
- Anastasiya A. Kasimova
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Nowshin S. Sharar
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Stephanie J. Ambrose
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, Australia
| | - Yuriy A. Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail M. Shneider
- M. M. Shemyakin and Y. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Olga Y. Timoshina
- M. M. Shemyakin and Y. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya V. Popova
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region, Russia
| | - Andrey V. Perepelov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Andrey S. Dmitrenok
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Li Yang Hsu
- Saw Swee Hock School of Public Health, National University of Singapore, Queenstown, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Queenstown, Singapore
| | - Ruth M. Hall
- School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, Australia
| | - Johanna J. Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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Wiradiputra MRD, Thirapanmethee K, Khuntayaporn P, Wanapaisan P, Chomnawang MT. Comparative genotypic characterization related to antibiotic resistance phenotypes of clinical carbapenem-resistant Acinetobacter baumannii MTC1106 (ST2) and MTC0619 (ST25). BMC Genomics 2023; 24:689. [PMID: 37978344 PMCID: PMC10655397 DOI: 10.1186/s12864-023-09734-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 10/11/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND The prevalence of Acinetobacter baumannii in nosocomial infections and its remarkable ability to develop antimicrobial resistance have been a critical issue in hospital settings. Here, we examined the genomic features related to resistance phenotype displayed by carbapenem-resistant A. baumannii (CRAB) MTC1106 (ST2) and MTC0619 (ST25). RESULTS Resistome analysis of both strains revealed that MTC1106 possessed higher numbers of antimicrobial resistance genes compared to MTC0619. Some of those genetic determinants were present in accordance with the susceptibility profile of the isolates. The predicted ISAba1 region upstream of blaOXA-23 gene was related to carbapenem resistance since this IS element was well-characterized to mediate overexpression of carbapenemase genes and eventually provided capability to confer resistance. Unlike MTC0619 strain, which only carried class B and D β-lactamase genes, MTC1106 strain also possessed blaTEM-1D, a class A β-lactamase. Regarding to aminoglycosides resistance, MTC0619 contained 5 related genes in which all of them belonged to three groups of aminoglycosides modifying enzyme (AME), namely, N-acetyltransferase (AAC), O-nucleotidyltransferase (ANT), and O-phosphotransferase (APH). On the other hand, MTC1106 lacked only the AAC of which found in MTC0619, yet it also carried an armA gene encoding for 16S rRNA methyltransferase. Two macrolides resistance genes, mph(E) and msr(E), were identified next to the armA gene of MTC1106 isolate in which they encoded for macrolide 2'-phosphotransferase and ABC-type efflux pump, respectively. Besides acquired resistance genes, some chromosomal genes and SNPs associated with resistance to fluoroquinolones (i.e. gyrA and parC) and colistin (i.e. pmrCAB, eptA, and emrAB) were observed. However, gene expression analysis suggested that the genetic determinants significantly contributing to low-level colistin resistance remained unclear. In addition, similar number of efflux pumps genes were identified in both lineages with only the absence of adeC, a part of adeABC RND-type multidrug efflux pump in MTC0619 strain. CONCLUSIONS We found that MTC1106 strain harbored more antimicrobial resistance genes and showed higher resistance to antibiotics than MTC0619 strain. Regarding genomic characterization, this study was likely the first genome comparative analysis of CARB that specifically included isolates belonging to ST2 and ST25 which were widely spread in Thailand. Taken altogether, this study suggests the importance to monitor the resistance status of circulating A. baumannii clones and identify genes that may contribute to shifting the resistance trend among isolates.
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Affiliation(s)
- Made Rai Dwitya Wiradiputra
- Antimicrobial Resistance Interdisciplinary Group (AmRIG), Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
- Biopharmaceutical Sciences Program, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Krit Thirapanmethee
- Antimicrobial Resistance Interdisciplinary Group (AmRIG), Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
- Department of Microbiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Piyatip Khuntayaporn
- Antimicrobial Resistance Interdisciplinary Group (AmRIG), Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
- Department of Microbiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Pagakrong Wanapaisan
- Antimicrobial Resistance Interdisciplinary Group (AmRIG), Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
- Department of Microbiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Mullika Traidej Chomnawang
- Antimicrobial Resistance Interdisciplinary Group (AmRIG), Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.
- Department of Microbiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.
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Harmer CJ, Nigro SJ, Hall RM. Acinetobacter baumannii GC2 Sublineage Carrying the aac( 6')- Im Amikacin, Netilmicin, and Tobramycin Resistance Gene Cassette. Microbiol Spectr 2023; 11:e0120423. [PMID: 37409961 PMCID: PMC10434200 DOI: 10.1128/spectrum.01204-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/09/2023] [Indexed: 07/07/2023] Open
Abstract
The aminoglycoside antibiotics amikacin, gentamicin, and tobramycin are important therapeutic options for Acinetobacter iinfections. Several genes that confer resistance to one or more of these antibiotics are prevalent in the globally distributed resistant clones of Acinetobacter baumannii, but the aac(6')-Im (aacA16) gene (amikacin, netilmicin, and tobramycin resistance), first reported in isolates from South Korea, has rarely been reported since. In this study, GC2 isolates (1999 to 2002) from Brisbane, Australia, carrying aac(6')-Im and belonging to the ST2:ST423:KL6:OCL1 type were identified and sequenced. The aac(6')-Im gene and surrounds have been incorporated into one end of the IS26-bounded AbGRI2 antibiotic resistance island and are accompanied by a characteristic 70.3-kbp deletion of adjacent chromosome. The compete genome of the 1999 isolate F46 (RBH46) includes only two copies of ISAba1 (in AbGRI1-3 and upstream of ampC) but later isolates, which differ from one another by <10 single nucleotide differences (SND), carry two to seven additional shared copies. Several complete GC2 genomes with aac(6')-Im in an AbGRI2 island (2004 to 2017; several countries) found in GenBank and two additional Australian A. baumannii isolates (2006) carry different gene sets, KL2, KL9, KL40, or KL52, at the capsule locus. These genomes include ISAba1 copies in a different set of shared locations. The distribution of SND between F46 and AYP-A2, a 2013 ST2:ST208:KL2:OCL1 isolate from Victoria, Australia, revealed that a 640-kbp segment that includes KL2 and the AbGRI1 resistance island replaces the corresponding region in F46. Over 1,000 A. baumannii draft genomes also include aac(6')-Im, indicating that it is currently globally disseminated and significantly underreported. IMPORTANCE Aminoglycosides are important therapeutic options for treatment of Acinetobacter infections. Here, we show that a little-known aminoglycoside resistance gene, aac(6')-Im (aacA16), that confers amikacin, netilmicin, and tobramycin resistance has been circulating undetected for many years in a sublineage of A. baumannii global clone 2 (GC2), generally with a second aminoglycoside resistance gene, aacC1, which confers resistance to gentamicin. These two genes are commonly found together in GC2 complete and draft genomes and globally distributed. One isolate appears to be ancestral, as its genome contains few ISAba1 copies, providing insight into the original source of this insertion sequence (IS), which is abundant in most GC2 isolates. Tracking ISAba1 spread can provide a simple means to track the development and ongoing evolution as well as the dissemination of specific lineages and detect the formation of many sublineages. The complete ancestral genome will provide an essential base point for tracking this process.
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Affiliation(s)
- Christopher J. Harmer
- School of Life and Environmental Sciences, The University of Sydney, New South Wales, Australia
| | - Steven J. Nigro
- School of Life and Environmental Sciences, The University of Sydney, New South Wales, Australia
| | - Ruth M. Hall
- School of Life and Environmental Sciences, The University of Sydney, New South Wales, Australia
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Libuit KG, Doughty EL, Otieno JR, Ambrosio F, Kapsak CJ, Smith EA, Wright SM, Scribner MR, Petit III RA, Mendes CI, Huergo M, Legacki G, Loreth C, Park DJ, Sevinsky JR. Accelerating bioinformatics implementation in public health. Microb Genom 2023; 9:mgen001051. [PMID: 37428142 PMCID: PMC10438813 DOI: 10.1099/mgen.0.001051] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/24/2023] [Indexed: 07/11/2023] Open
Abstract
We have adopted an open bioinformatics ecosystem to address the challenges of bioinformatics implementation in public health laboratories (PHLs). Bioinformatics implementation for public health requires practitioners to undertake standardized bioinformatic analyses and generate reproducible, validated and auditable results. It is essential that data storage and analysis are scalable, portable and secure, and that implementation of bioinformatics fits within the operational constraints of the laboratory. We address these requirements using Terra, a web-based data analysis platform with a graphical user interface connecting users to bioinformatics analyses without the use of code. We have developed bioinformatics workflows for use with Terra that specifically meet the needs of public health practitioners. These Theiagen workflows perform genome assembly, quality control, and characterization, as well as construction of phylogeny for insights into genomic epidemiology. Additonally, these workflows use open-source containerized software and the WDL workflow language to ensure standardization and interoperability with other bioinformatics solutions, whilst being adaptable by the user. They are all open source and publicly available in Dockstore with the version-controlled code available in public GitHub repositories. They have been written to generate outputs in standardized file formats to allow for further downstream analysis and visualization with separate genomic epidemiology software. Testament to this solution meeting the requirements for bioinformatic implementation in public health, Theiagen workflows have collectively been used for over 5 million sample analyses in the last 2 years by over 90 public health laboratories in at least 40 different countries. Continued adoption of technological innovations and development of further workflows will ensure that this ecosystem continues to benefit PHLs.
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Affiliation(s)
- Kevin G. Libuit
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Emma L. Doughty
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - James R. Otieno
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Frank Ambrosio
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Curtis J. Kapsak
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Emily A. Smith
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Sage M. Wright
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Michelle R. Scribner
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Robert A. Petit III
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
- Wyoming Public Health Laboratory, 208 S College Dr, Cheyenne, WY 82007, USA
| | - Catarina Inês Mendes
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Marcela Huergo
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Gregory Legacki
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
| | - Christine Loreth
- Broad Institute of Harvard and MIT, 415 Main St, Cambridge, MA 02142, USA
| | - Daniel J. Park
- Broad Institute of Harvard and MIT, 415 Main St, Cambridge, MA 02142, USA
| | - Joel R. Sevinsky
- Theiagen Genomics, Suite 400, 1745 Shea Center Drive, Highlands Ranch, CO, 80129, USA
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Neto S, Vieira A, Oliveira H, Espiña B. Assessing Acinetobacter baumannii virulence and treatment with a bacteriophage using zebrafish embryos. FASEB J 2023; 37:e23013. [PMID: 37289094 DOI: 10.1096/fj.202300385r] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/10/2023] [Accepted: 05/19/2023] [Indexed: 06/09/2023]
Abstract
Acinetobacter baumannii is the leading bacteria causative of nosocomial infections, with high fatality rates, mostly due to their multi-resistance to antibiotics. The capsular polysaccharide (k-type) is a major virulence factor. Bacteriophages are viruses that specifically infect bacteria and have been used to control drug-resistant bacterial pathogens. In particular, A. baumannii phages can recognize specific capsules, from a diversity of >125 that exist. This high specificity demands the in vivo identification of the most virulent A. baumannii k-types that need to be targeted by phage therapy. Currently, the zebrafish embryo has particularly attained interest for in vivo infection modeling. In this study, an A. baumannii infection was successfully established, through the bath immersion of tail-injured zebrafish embryos, to study the virulence of eight capsule types (K1, K2, K9, K32, K38, K44, K45, and K67). The model revealed itself as capable of discerning the most virulent (K2, K9, K32, and K45), middle (K1, K38, and K67), and the less virulent (K44) strains. Additionally, the infection of the most virulent strains was controlled in vivo resorting to the same technique, with previously identified phages (K2, K9, K32, and K45 phages). Phage treatments were able to increase the average survival from 35.2% to up to 74.1% (K32 strain). All the phages performed equally well. Collectively, the results show the potential of the model to not only evaluate virulence of bacteria such as A. baumannii but also assess novel treatments' effectiveness.
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Affiliation(s)
- Sofia Neto
- International Iberian Nanotechnology Laboratory (INL), Braga, Portugal
- CEB-Center of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS-Associate Laboratory, Guimarães, Portugal
| | - Ana Vieira
- International Iberian Nanotechnology Laboratory (INL), Braga, Portugal
| | - Hugo Oliveira
- CEB-Center of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS-Associate Laboratory, Guimarães, Portugal
| | - Begoña Espiña
- International Iberian Nanotechnology Laboratory (INL), Braga, Portugal
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Sykes EME, Mateo-Estrada V, Zhanel G, Dettman J, Chapados J, Gerdis S, Akineden Ö, Khan IIU, Castillo-Ramírez S, Kumar A. Emergence of ADC-5 Cephalosporinase in environmental Acinetobacter baumannii from a German tank milk with a novel Sequence Type. Access Microbiol 2023; 5:acmi000485.v3. [PMID: 37424542 PMCID: PMC10323797 DOI: 10.1099/acmi.0.000485.v3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 05/15/2023] [Indexed: 07/11/2023] Open
Abstract
Bacteria resistant to antibiotics arguably pose the greatest threat to human health in the twenty-first century. One such bacterium that typifies antibiotic resistance is Acinetobacter baumannii . Frequently, hospital strains of A. baumannii display multidrug resistant (MDR) or extensively drug resistant (XDR) phenotypes, often requiring the use of last resort antibiotics for treatment. In addition to hospital settings, A. baumannii has been isolated from many highly divergent sources including wastewater treatment plant effluent, soil, and agricultural run-off with global distribution. However, such isolates remain poorly characterized. In this study, we characterized a strain of A. baumannii, AB341-IK15, isolated from bulk tank milk in Germany that demonstrated resistance to ceftazidime and intermediate resistance to ceftriaxone and piperacillin/tazobactam. Further genetic characterization identified an ADC-5 cephalosporinase, first incidence in an environmental isolate; and an OXA-408 oxacillinase that may contribute to this phenotype. Interestingly, AB341-IK15 is of a novel sequence type. This research underscores the importance of studying isolates of A. baumannii of non-clinical origin to understand the antibiotic resistance and virulence potential of environmental isolates of A. baumannii as well to understand the diversity of this species.
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Affiliation(s)
- Ellen M. E. Sykes
- Department of Microbiology, University of Manitoba Winnipeg, Winnipeg, Canada
| | - Valeria Mateo-Estrada
- Programa de Genómica Evolutiva, Centro de Ciencias Génomicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - George Zhanel
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Canada
| | - Jeremy Dettman
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Canada
| | - Julie Chapados
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Canada
| | - Suzanne Gerdis
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Canada
| | - Ömer Akineden
- Institute of Veterinary Food Science, University of Giessen, Giessen, Germany
| | - Izhar I. U. Khan
- Ottawa Research and Development Centre (ORDC), Agriculture and Agri-Food Canada, Ottawa, Canada
| | - Santiago Castillo-Ramírez
- Programa de Genómica Evolutiva, Centro de Ciencias Génomicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Ayush Kumar
- Department of Microbiology, University of Manitoba Winnipeg, Winnipeg, Canada
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38
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Roshini J, Patro LPP, Sundaresan S, Rathinavelan T. Structural diversity among Acinetobacter baumannii K-antigens and its implication in the in silico serotyping. Front Microbiol 2023; 14:1191542. [PMID: 37415807 PMCID: PMC10320297 DOI: 10.3389/fmicb.2023.1191542] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/30/2023] [Indexed: 07/08/2023] Open
Abstract
Acinetobacter baumannii is an emerging opportunistic pathogen. It exhibits multi-, extreme-, and pan-drug resistance against several classes of antibiotics. Capsular polysaccharide (CPS or K-antigen) is one of the major virulence factors which aids A. baumannii in evading the host immune system. K-antigens of A. baumannii exploit the Wzx/Wzy-dependent pathway that involves 13 different proteins for its assembly and transport onto the outer membrane. A total of 64 (out of 237 K-locus(KL) types) known K-antigen sugar repeating structures are discussed here and are classified into seven groups based on their initial sugars, QuiNAc4NAc, GalNAc, GlcNAc, Gal, QuiNAc/FucNAc, FucNAc, and GlcNAc along with Leg5Ac7Ac/Leg5Ac7R. Thus, the corresponding seven initializing glycosyltransferases (ItrA1, ItrA2, ItrA3, ItrA4, ItrB1, ItrB3, and ItrA3 along with ItrB2) exhibit serotype specificity. The modeled 3D-structural repository of the 64 K-antigens can be accessed at https://project.iith.ac.in/ABSD/k_antigen.html. The topology of K-antigens further reveals the presence of 2-6 and 0-4 sugar monomers in the main and side chains, respectively. The presence of negatively (predominant) or neutrally charged K-antigens is observed in A. baumannii. Such diversity in the K-antigen sugar composition provides the K-typing specificity (viz., 18-69% in terms of reliability) for Wza, Wzb, Wzc, Wzx, and Wzy proteins involved in the Wzx/Wzy-dependent pathway. Interestingly, the degree of uniqueness of these proteins among different K-types is estimated to be 76.79%, considering the 237 reference sequences. This article summarizes the A. baumannii K-antigen structural diversity and creation of a K-antigen digital repository and provides a systematic analysis of the K-antigen assembly and transportation marker proteins.
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Mangioni D, Fox V, Chatenoud L, Bolis M, Bottino N, Cariani L, Gentiloni Silverj F, Matinato C, Monti G, Muscatello A, Teri A, Terranova L, Piatti A, Gori A, Grasselli G, Stocchetti N, Alteri C, Bandera A. Genomic Characterization of Carbapenem-Resistant Acinetobacter baumannii (CRAB) in Mechanically Ventilated COVID-19 Patients and Impact of Infection Control Measures on Reducing CRAB Circulation during the Second Wave of the SARS-CoV-2 Pandemic in Milan, Italy. Microbiol Spectr 2023; 11:e0020923. [PMID: 36976013 PMCID: PMC10100775 DOI: 10.1128/spectrum.00209-23] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 03/06/2023] [Indexed: 03/29/2023] Open
Abstract
COVID-19 has significantly affected hospital infection prevention and control (IPC) practices, especially in intensive care units (ICUs). This frequently caused dissemination of multidrug-resistant organisms (MDROs), including carbapenem-resistant Acinetobacter baumannii (CRAB). Here, we report the management of a CRAB outbreak in a large ICU COVID-19 hub Hospital in Italy, together with retrospective genotypic analysis by whole-genome sequencing (WGS). Bacterial strains obtained from severe COVID-19 mechanically ventilated patients diagnosed with CRAB infection or colonization between October 2020 and May 2021 were analyzed by WGS to assess antimicrobial resistance and virulence genes, along with mobile genetic elements. Phylogenetic analysis in combination with epidemiological data was used to identify putative transmission chains. CRAB infections and colonization were diagnosed in 14/40 (35%) and 26/40 (65%) cases, respectively, with isolation within 48 h from admission in 7 cases (17.5%). All CRAB strains belonged to Pasteur sequence type 2 (ST2) and 5 different Oxford STs and presented blaOXA-23 gene-carrying Tn2006 transposons. Phylogenetic analysis revealed the existence of four transmission chains inside and among ICUs, circulating mainly between November and January 2021. A tailored IPC strategy was composed of a 5-point bundle, including ICU modules' temporary conversion to CRAB-ICUs and dynamic reopening, with limited impact on ICU admission rate. After its implementation, no CRAB transmission chains were detected. Our study underlies the potentiality of integrating classical epidemiological studies with genomic investigation to identify transmission routes during outbreaks, which could represent a valuable tool to ensure IPC strategies and prevent the spread of MDROs. IMPORTANCE Infection prevention and control (IPC) practices are of paramount importance for preventing the spread of multidrug-resistant organisms (MDROs) in hospitals, especially in the intensive care unit (ICU). Whole-genome sequencing (WGS) is seen as a promising tool for IPC, but its employment is currently still limited. COVID-19 pandemics have posed dramatic challenges in IPC practices, causing worldwide several outbreaks of MDROs, including carbapenem-resistant Acinetobacter baumannii (CRAB). We present the management of a CRAB outbreak in a large ICU COVID-19 hub hospital in Italy using a tailored IPC strategy that allowed us to contain CRAB transmission while preventing ICU closure during a critical pandemic period. The analysis of clinical and epidemiological data coupled with retrospective genotypic analysis by WGS identified different putative transmission chains and confirmed the effectiveness of the IPC strategy implemented. This could be a promising approach for future IPC strategies.
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Affiliation(s)
- Davide Mangioni
- Infectious Diseases Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milano, Milan, Italy
| | - Valeria Fox
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | | | - Matteo Bolis
- Infectious Diseases Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Nicola Bottino
- Department of Anaesthesia, Critical Care and Emergency, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Lisa Cariani
- Microbiology Laboratory, Clinical Laboratory, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | | | - Caterina Matinato
- Microbiology Laboratory, Clinical Laboratory, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Gianpaola Monti
- Department of Anesthesia and Intensive Care, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Antonio Muscatello
- Infectious Diseases Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Antonio Teri
- Microbiology Laboratory, Clinical Laboratory, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Leonardo Terranova
- Department of Internal Medicine, Respiratory Unit and Adult Cystic Fibrosis Center, Foundation IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alessandra Piatti
- Medical Direction, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Andrea Gori
- Infectious Diseases Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milano, Milan, Italy
| | - Giacomo Grasselli
- Department of Pathophysiology and Transplantation, University of Milano, Milan, Italy
- Department of Anaesthesia, Critical Care and Emergency, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Nino Stocchetti
- Department of Pathophysiology and Transplantation, University of Milano, Milan, Italy
- Department of Anaesthesia and Critical Care, Neuroscience Intensive Care Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Claudia Alteri
- Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Alessandra Bandera
- Infectious Diseases Unit, Foundation IRCCS Ca’ Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milano, Milan, Italy
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Slarve M, Reyna Z, Burk E, Ruiz-Delgado J, Li R, Yan J, Luna B, Spellberg B. Therapeutic, Humanized Monoclonal Antibody Exhibits Broad Binding and Protective Efficacy against Acinetobacter baumannii. Antimicrob Agents Chemother 2023; 67:e0008623. [PMID: 36853012 PMCID: PMC10019318 DOI: 10.1128/aac.00086-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 02/08/2023] [Indexed: 03/01/2023] Open
Abstract
Acinetobacter baumannii is an extremely drug-resistant pathogen necessitating the development of new therapies. We seek to generate a cocktail of monoclonal antibodies (MAbs) that can target the full diversity of A. baumannii isolates. We have newly identified the antibody MAb5. Here, we demonstrate that MAb5 has broad binding against U.S. (n = 300) and international (n = 250) isolates (72.24% and 28.76%, respectively), likely targets O-antigen capsular carbohydrates, and exhibits protective efficacy in vivo.
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Affiliation(s)
- Matthew Slarve
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Zeferino Reyna
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Elizabeth Burk
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Juan Ruiz-Delgado
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Rachel Li
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Jun Yan
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Brian Luna
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of USC, Los Angeles, California, USA
| | - Brad Spellberg
- Los Angeles County-USC (LAC+USC) Medical Center, Los Angeles, California, USA
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Timoshina OY, Kasimova AA, Shneider MM, Arbatsky NP, Shashkov AS, Shelenkov AA, Mikhailova YV, Popova AV, Hall RM, Knirel YA, Kenyon JJ. Loss of a Branch Sugar in the Acinetobacter baumannii K3-Type Capsular Polysaccharide Due To Frameshifts in the gtr6 Glycosyltransferase Gene Leads To Susceptibility To Phage APK37.1. Microbiol Spectr 2023; 11:e0363122. [PMID: 36651782 PMCID: PMC9927144 DOI: 10.1128/spectrum.03631-22] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 12/21/2022] [Indexed: 01/19/2023] Open
Abstract
The type of capsular polysaccharide (CPS) on the cell surface of Acinetobacter baumannii can determine the specificity of lytic bacteriophage under consideration for therapeutic use. Here, we report the isolation of a phage on an extensively antibiotic resistant ST2 A. baumannii isolate AB5001 that carries the KL3 CPS biosynthesis gene cluster predicting a K3-type CPS. As the phage did not infect isolates carrying KL3 or KL22 and known to produce K3 CPS, the structure of the CPS isolated from A. baumannii AB5001 was determined. AB5001 produced a variant CPS form, K3-v1, that lacks the β-d-GlсpNAc side chain attached to the d-Galp residue in the K3 structure. Inspection of the KL3 sequence in the genomes of AB5001 and other phage-susceptible isolates with a KL3 locus revealed single-base deletions in gtr6, causing loss of the Gtr6 glycosyltransferase that adds the missing d-GlсpNAc side chain to the K3 CPS. Hence, the presence of this sugar profoundly restricts the ability of the phage to digest the CPS. The 41-kb linear double-stranded DNA (dsDNA) phage genome was identical to the genome of a phage isolated on a K37-producing isolate and thus was named APK37.1. APK37.1 also infected isolates carrying KL116. Consistent with this, K3-v1 resembles the K37 and K116 structures. APK37.1 is a Friunavirus belonging to the Autographiviridae family. The phage-encoded tail spike depolymerase DpoAPK37.1 was not closely related to Dpo encoded by other sequenced Friunaviruses, including APK37 and APK116. IMPORTANCE Lytic bacteriophage have potential for the treatment of otherwise untreatable extensively antibiotic-resistant bacteria. For Acinetobacter baumannii, most phage exhibit specificity for the type of capsular polysaccharide (CPS) produced on the cell surface. However, resistance can arise via mutations in CPS genes that abolish this phage receptor. Here, we show that single-base deletions in a CPS gene result in alteration of the final structure rather than deletion of the capsule layer and hence affect the ability of a newly reported podophage to infect strains producing the K3 CPS.
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Affiliation(s)
- Olga Y. Timoshina
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anastasiya A. Kasimova
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail M. Shneider
- M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Nikolay P. Arbatsky
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexander S. Shashkov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | | | | | - Anastasiya V. Popova
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Russia
| | - Ruth M. Hall
- School of Life and Environmental Science, University of Sydney, Sydney, Australia
| | - Yuriy A. Knirel
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Johanna J. Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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Valcek A, Philippe C, Whiteway C, Robino E, Nesporova K, Bové M, Coenye T, De Pooter T, De Coster W, Strazisar M, Van der Henst C. Phenotypic Characterization and Heterogeneity among Modern Clinical Isolates of Acinetobacter baumannii. Microbiol Spectr 2023; 11:e0306122. [PMID: 36475894 PMCID: PMC9927488 DOI: 10.1128/spectrum.03061-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022] Open
Abstract
Acinetobacter baumannii is an opportunistic pathogenic bacterium prioritized by WHO and CDC because of its increasing antibiotic resistance. Heterogeneity among strains represents the hallmark of A. baumannii bacteria. We wondered to what extent extensively used strains, so-called reference strains, reflect the dynamic nature and intrinsic heterogeneity of these bacteria. We analyzed multiple phenotypic traits of 43 nonredundant, modern, and multidrug-resistant, extensively drug-resistant, and pandrug-resistant clinical isolates and broadly used strains of A. baumannii. Comparison of these isolates at the genetic and phenotypic levels confirmed a high degree of heterogeneity. Importantly, we observed that a significant portion of modern clinical isolates strongly differs from several historically established strains in the light of colony morphology, cellular density, capsule production, natural transformability, and in vivo virulence. The significant differences between modern clinical isolates of A. baumannii and established strains could hamper the study of A. baumannii, especially concerning its virulence and resistance mechanisms. Hence, we propose a variable collection of modern clinical isolates that are characterized at the genetic and phenotypic levels, covering a wide range of the phenotypic spectrum, with six different macrocolony type groups, from avirulent to hypervirulent phenotypes, and with naturally noncapsulated to hypermucoid strains, with intermediate phenotypes as well. Strain-specific mechanistic observations remain interesting per se, and established "reference" strains have undoubtedly been shown to be very useful to study basic mechanisms of A. baumannii biology. However, any study based on a specific strain of A. baumannii should be compared to modern and clinically relevant isolates. IMPORTANCE Acinetobacter baumannii is a bacterium prioritized by the CDC and WHO because of its increasing antibiotic resistance, leading to treatment failures. The hallmark of this pathogen is the high heterogeneity observed among isolates, due to a very dynamic genome. In this context, we tested if a subset of broadly used isolates, considered "reference" strains, was reflecting the genetic and phenotypic diversity found among currently circulating clinical isolates. We observed that the so-called reference strains do not cover the whole diversity of the modern clinical isolates. While formerly established strains successfully generated a strong base of knowledge in the A. baumannii field and beyond, our study shows that a rational choice of strain, related to a specific biological question, should be taken into consideration. Any data obtained with historically established strains should also be compared to modern and clinically relevant isolates, especially concerning drug screening, resistance, and virulence contexts.
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Affiliation(s)
- Adam Valcek
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Chantal Philippe
- Research Unit in the Biology of Microorganisms (URBM), NARILIS, University of Namur (UNamur), Namur, Belgium
| | - Clémence Whiteway
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Etienne Robino
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Kristina Nesporova
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Mona Bové
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
| | - Tim De Pooter
- Neuromics Support Facility, VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Wouter De Coster
- Applied and Translational Neurogenomics Group, VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Applied and Translational Neurogenomics Group, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Mojca Strazisar
- Neuromics Support Facility, VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Charles Van der Henst
- Microbial Resistance and Drug Discovery, VIB-VUB Center for Structural Biology, VIB, Flanders Institute for Biotechnology, Brussels, Belgium
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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43
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Rakovitsky N, Lurie-Weinberger MN, Hameir A, Wulffhart L, Keren Paz A, Schwartz D, Carmeli Y. Phenotypic and Genomic Characterization of Nine String-Positive Carbapenem-Resistant Acinetobacter baumannii Isolates from Israel. Microbiol Spectr 2023; 11:e0300222. [PMID: 36719216 PMCID: PMC10100839 DOI: 10.1128/spectrum.03002-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 01/09/2023] [Indexed: 02/01/2023] Open
Abstract
A positive "string test" indicates the ability of bacterial colonies grown on agar plates to form viscous strings of >5 mm when stretched. This phenotype is strongly associated with hypervirulence in Klebsiella pneumoniae but has never been described in carbapenem-resistant Acinetobacter baumannii (CRAB), an emerging human pathogen of high clinical significance. In this work, we screened 1,000 CRAB isolates, among which we identified and characterized 9 string-positive CRAB (stCRAB) isolates. Phenotypic and genotypic analyses revealed that the isolates were not phylogenetically related and possessed different antibiotic resistance and virulence profiles. Transmission electron microscopy (TEM) showed the presence of capsule in string-positive isolates. String-positive isolates were more motile but did not form more biofilm than non-string-positive isolates. They were less virulent in a murine thigh fitness model and a Galleria mellonella survival assay. In conclusion, here, we describe string-positive A. baumannii isolates and their phenotypic and molecular characteristics. We found that unlike K. pneumoniae, stCRAB isolates were not associated with increased virulence. IMPORTANCE Acinetobacter baumannii has been considered a major health care threat in recent years. Despite many efforts, the pathogenesis and molecular mechanism of A. baumannii virulence remain poorly understood. Moreover, the plasticity of its genome frequently gives rise to new and more virulent isolates. Our current study is of significant importance as it concerns a previously undescribed A. baumannii phenotype. The string-positive phenotype is strongly associated with increased fitness and virulence in other Gram-negative bacteria such as K. pneumoniae. Although no clear correlation with virulence or fitness was found in our 9 stCRAB isolates, this could have been due to the limited statistical power of our research. We suggest that this phenotype should be taken into consideration as due to its genome plasticity, the next change can give rise to string-positive and hypervirulent strains, as is known for K. pneumoniae. Additional future research is needed regarding its possible consequences.
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Affiliation(s)
- Nadya Rakovitsky
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
| | - Mor N. Lurie-Weinberger
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
| | - Amichay Hameir
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
| | - Liat Wulffhart
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
| | - Alona Keren Paz
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
| | - David Schwartz
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
| | - Yehuda Carmeli
- National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Wang Y, Zhou J, Liu H, Wang Q, Zhang P, Zhu J, Zhao D, Wu X, Yu Y, Jiang Y. Emergence of high-level colistin resistance mediated by multiple determinants, including mcr-1.1, mcr-8.2 and crrB mutations, combined with tigecycline resistance in an ST656 Klebsiella pneumoniae. Front Cell Infect Microbiol 2023; 13:1122532. [PMID: 36779188 PMCID: PMC9909390 DOI: 10.3389/fcimb.2023.1122532] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 01/16/2023] [Indexed: 01/27/2023] Open
Abstract
Colistin and tigecycline are usually regarded as the last resort for multidrug-resistant Klebsiella pneumoniae infection treatment. Emergence of colistin and tigecycline resistance poses a global healthcare challenge and is associated with high mortality due to limited therapeutic options. Here, we report the ST656 extensively drug-resistant K. pneumoniae strain KP15-652, which was isolated from a patient's urine in China. Antimicrobial susceptibility testing showed it to be resistant to tigecycline, amikacin, levofloxacin, ciprofloxacin, and high-level colistin resistance (> 2048 mg/L). Whole-genome sequencing revealed that it harbors one chromosome and seven plasmids, including four plasmids carrying multiple acquired resistance genes. Transformation/conjugation tests and plasmid curing assays confirmed that mcr-1.1, mcr-8.2 and crrB mutations are responsible for the high-level colistin resistance and that a series of efflux pump genes, such as tmexCD1-toprJ1, tet(A) and tet(M), contribute to tigecycline resistance. mcr-1.1 and tet(M) are located on an IncX1 plasmid, which has conjugation transfer potential. mcr-8.2 and tet(A) are located on a multireplicon IncR/IncN plasmid but unable to be transferred via conjugation. Moreover, another conjugable and fusion plasmid carries the tmexCD1-toprJ1 gene cluster, which may have arisen due to IS26-mediated replicative transposition based on 8-bp target-site duplications. Importantly, a complex class 1 integron carrying various resistance genes was detected on this fusion plasmid. In conclusion, it is possible that the high-level of colistin resistance is caused by the accumulated effect of several factors on the chromosome and mcr-carrying plasmids, combined with many other resistances, including tigecycline. Effective surveillance should be performed to prevent further dissemination.
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Affiliation(s)
- Yanfei Wang
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Junxin Zhou
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Haiyang Liu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Qian Wang
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Department of General Practice, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ping Zhang
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jingyi Zhu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Dongdong Zhao
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xueqing Wu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yunsong Yu
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- *Correspondence: Yan Jiang, ; Yunsong Yu,
| | - Yan Jiang
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- *Correspondence: Yan Jiang, ; Yunsong Yu,
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Intensification in Genetic Information and Acquisition of Resistant Genes in Genome of Acinetobacter baumannii: A Pan-Genomic Analysis. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3186343. [PMID: 36605106 PMCID: PMC9810410 DOI: 10.1155/2022/3186343] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 11/02/2022] [Accepted: 12/03/2022] [Indexed: 12/29/2022]
Abstract
Acinetobacter baumannii (A. baumannii) attributes 26% of the mortality rate in hospitalized patients, and the percentage can rise to 46 in patients admitted to ICU as it is a major cause of ventilator-associated pneumonia. It has been nominated as the critical priority organism by WHO for which new therapeutic drugs are urgently required. To understand the genomic identification of different strains, antimicrobial resistance patterns, and epidemiological typing of organisms, whole-genome sequencing (WGS) analysis provides insight to explore new epitopes to develop new drugs against the organism. Therefore, the study is aimed at investigating the whole genome sequence of A. baumannii strains to report the new intensifications in its genomic profile. The genome sequences were retrieved from the NCBI database system. Pan-genome BPGA (Bacterial Pan-genome Analysis Tool) was used to analyze the core, pan, and species-specific genome analysis. The pan and core genome curves were extrapolated using the empirical power law equation f(x) = a.xb and the exponential equation f1(x) = c.e (d.x). To identify the resistant genes with resistant mutations against antibiotics, ResFinder and Galaxy Community hub bioinformatics tools were used. According to pan-genome analysis, there were 2227 core genes present in each species of the A. baumannii genome. Furthermore, the number of accessory genes ranged from 1182 to 1460, and the unique genes in the genome were 931. There were 325 exclusively absent genes in the genome of Acinetobacter baumannii. The pan-genome analysis showed that there is a 5-fold increase in the genome of A. baumannii in 5 years, and the genome is still open. There is the addition of multiple unique genes; among them, genes participating in the function of information and processing are increased.
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Rahman A, Styczynski A, Khaleque A, Hossain SA, Sadique A, Hossain A, Jain M, Tabassum SN, Khan F, Bhuiyan MSS, Alam J, Khandakar A, Kamruzzaman M, Ahsan CR, Kashem SBA, Chowdhury MEH, Hossain M. Genomic landscape of prominent XDR Acinetobacter clonal complexes from Dhaka, Bangladesh. BMC Genomics 2022; 23:802. [PMID: 36471260 PMCID: PMC9721023 DOI: 10.1186/s12864-022-08991-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 11/05/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Acinetobacter calcoaceticus-A. baumannii (ACB) complex pathogens are known for their prevalence in nosocomial infections and extensive antimicrobial resistance (AMR) capabilities. While genomic studies worldwide have elucidated the genetic context of antibiotic resistance in major international clones (ICs) of clinical Acinetobacter spp., not much information is available from Bangladesh. In this study, we analysed the AMR profiles of 63 ACB complex strains collected from Dhaka, Bangladesh. Following this, we generated draft genomes of 15 of these strains to understand the prevalence and genomic environments of AMR, virulence and mobilization associated genes in different Acinetobacter clones. RESULTS Around 84% (n = 53) of the strains were extensively drug resistant (XDR) with two showing pan-drug resistance. Draft genomes generated for 15 strains confirmed 14 to be A. baumannii while one was A. nosocomialis. Most A. baumannii genomes fell under three clonal complexes (CCs): the globally dominant CC1 and CC2, and CC10; one strain had a novel sequence type (ST). AMR phenotype-genotype agreement was observed and the genomes contained various beta-lactamase genes including blaOXA-23 (n = 12), blaOXA-66 (n = 6), and blaNDM-1 (n = 3). All genomes displayed roughly similar virulomes, however some virulence genes such as the Acinetobactin bauA and the type IV pilus gene pilA displayed high genetic variability. CC2 strains carried highest levels of plasmidic gene content and possessed conjugative elements carrying AMR genes, virulence factors and insertion sequences. CONCLUSION This study presents the first comparative genomic analysis of XDR clinical Acinetobacter spp. from Bangladesh. It highlights the prevalence of different classes of beta-lactamases, mobilome-derived heterogeneity in genetic architecture and virulence gene variability in prominent Acinetobacter clonal complexes in the country. The findings of this study would be valuable in understanding the genomic epidemiology of A. baumannii clones and their association with closely related pathogenic species like A. nosocomialis in Bangladesh.
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Affiliation(s)
- Aura Rahman
- NSU Genome Research Institute, North South University, Dhaka, Bangladesh
| | - Ashley Styczynski
- Division of Infectious Diseases and Geographic Medicine, School of Medicine, Stanford University, Palo Alto, California, USA
| | - Abdul Khaleque
- Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | | | - Abdus Sadique
- NSU Genome Research Institute, North South University, Dhaka, Bangladesh
| | - Arman Hossain
- Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | - Mukesh Jain
- The Hormone Lab & Infertility Centre, Dhaka, Bangladesh
| | | | - Fahad Khan
- NSU Genome Research Institute, North South University, Dhaka, Bangladesh
- Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | - Mohammad Sami Salman Bhuiyan
- NSU Genome Research Institute, North South University, Dhaka, Bangladesh
- Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | - Jahidul Alam
- NSU Genome Research Institute, North South University, Dhaka, Bangladesh
| | - Amith Khandakar
- Department of Electrical Engineering, Qatar University, Doha, 2713, Qatar
| | | | | | - Saad Bin Abul Kashem
- Department of Computer Sciences, AFG College with the University of Aberdeen, Doha, Qatar.
| | | | - Maqsud Hossain
- NSU Genome Research Institute, North South University, Dhaka, Bangladesh.
- Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh.
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Rafei R, Koong J, Osman M, Al Atrouni A, Hamze M, Hamidian M. Analysis of pCl107 a large plasmid carried by an ST25 Acinetobacter baumannii strain reveals a complex evolutionary history and links to multiple antibiotic resistance and metabolic pathways. FEMS MICROBES 2022; 3:xtac027. [PMID: 37332503 PMCID: PMC10117892 DOI: 10.1093/femsmc/xtac027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/13/2022] [Accepted: 11/14/2022] [Indexed: 09/14/2023] Open
Abstract
Acinetobacter baumannii has successfully spread during the last decades as one of the main critically important pathogens. However, many aspects including plasmids, are still under-investigated. Here, we report the complete sequence of an Acinetobacter baumannii strain, belonging to the ST25IP (Institut Pasteur) sequence type recovered in 2012 in Lebanon, using a combination of Illumina MiSeq and Oxford Nanopore sequencing and a hybrid assembly approach. This strain (Cl107) carries a 198 kb plasmid called pCl107 that encodes the MPFI conjugative transfer system. The plasmid carries the aacA1, aacC2, sul2, strAB, and tetA(B) antibiotic resistance genes. pCl107 region encompassing the sul2, strAB, tetA(B) is closely related to AbGRI1 chromosomal resistance islands, which are widespread in A. baumannii strains belonging to Global Clone 2. The resistance region found in pCl107 is one of the missing links in the evolutionary history of the AbGRI1 islands. pCl107 also contains a BREX Type 1 region and represents one of the two main evolution patterns observed in BREX clusters found in plasmids related to pCl107. pCl107 also harbours a ptx phosphonate metabolism module, which plays an ancestral structure compared to other large plasmids in ST25 strains. While the uric acid metabolic module found in pCl107 is incomplete, we identified possible ancestors from plasmids and chromosomes of Acinetobacter spp. Our analyses indicate a complex evolutionary history of plasmids related to pCl107 with many links to multiple antibiotic resistance and metabolic pathways.
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Affiliation(s)
- Rayane Rafei
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Science & Technology, Faculty of Public Health, Lebanese University, Tripoli 1300, Lebanon
| | - Jonathan Koong
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo NSW 2007, Australia
| | - Marwan Osman
- Cornell Atkinson Center for Sustainability, Cornell University, Ithaca, NY 14853, United States
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, United States
| | - Ahmad Al Atrouni
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Science & Technology, Faculty of Public Health, Lebanese University, Tripoli 1300, Lebanon
| | - Monzer Hamze
- Laboratoire Microbiologie Santé et Environnement (LMSE), Doctoral School of Science & Technology, Faculty of Public Health, Lebanese University, Tripoli 1300, Lebanon
| | - Mehrad Hamidian
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo NSW 2007, Australia
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Brito BP, Koong J, Wozniak A, Opazo-Capurro A, To J, Garcia P, Hamidian M. Genomic Analysis of Carbapenem-Resistant Acinetobacter baumannii Strains Recovered from Chilean Hospitals Reveals Lineages Specific to South America and Multiple Routes for Acquisition of Antibiotic Resistance Genes. Microbiol Spectr 2022; 10:e0246322. [PMID: 36154439 PMCID: PMC9602995 DOI: 10.1128/spectrum.02463-22] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 09/09/2022] [Indexed: 01/04/2023] Open
Abstract
Carbapenem-resistant Acinetobacter baumannii (CRAb) is a public health threat accounting for a significant number of hospital-acquired infections. Despite the importance of this pathogen, there is scarce literature on A. baumannii molecular epidemiology and evolutionary pathways relevant to resistance emergence in South American strains. We analyzed the genomic context of 34 CRAb isolates recovered from clinical samples between 2010 and 2013 from two hospitals in Santiago, Chile, using whole-genome sequencing. Several Institut Pasteur scheme sequence types (STs) were identified among the 34 genomes studied here, including ST1, ST15, ST79, ST162, and ST109. No ST2 (the most widespread sequence type) strain was detected. Chilean isolates were phylogenetically closely related, forming lineages specific to South America (e.g., ST1, ST79, and ST15). The genomic contexts of the resistance genes were diverse: while genes were present in a plasmid in ST15 strains, all genes were chromosomal in ST79 strains. Different variants of a small Rep_3 plasmid played a central role in the acquisition of the oxa58 carbapenem and aacC2 aminoglycoside resistance genes in ST1, ST15, and ST79 strains. The aacC2 gene along with blaTEM were found in a novel transposon named Tn6925 here. Variants of Tn7 were also found to play an important role in the acquisition of the aadA1 and dfrA1 genes. This work draws a detailed picture of the genetic context of antibiotic resistance genes in a set of carbapenem-resistant A. baumannii strains recovered from two Chilean hospitals and reveals a complex evolutionary picture of antibiotic resistance gene acquisition events via multiple routes involving several mobile genetic elements. IMPORTANCE Treating infections caused by carbapenem-resistant A. baumannii (CRAb) has become a global challenge given that CRAb strains are also often resistant to a wide range of antibiotics. Analysis of whole-genome sequence data is now a standard approach for studying the genomic context of antibiotic resistance genes; however, genome sequence data from South American countries are scarce. Here, phylogenetic and genomic analyses of 34 CRAb strains recovered from 2010 to 2013 from two Chilean hospitals revealed a complex picture leading to the generation of resistant lineages specific to South America. From these isolates, we characterized several mobile genetic elements, some of which are described for the first time. The genome sequences and analyses presented here further our understanding of the mechanisms leading to multiple-drug resistance, extensive drug resistance, and pandrug resistance phenotypes in South America. Therefore, this is a significant contribution to elucidating the global molecular epidemiology of CRAb.
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Affiliation(s)
- Barbara P. Brito
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
| | - Jonathan Koong
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
| | - Aniela Wozniak
- Laboratory of Microbiology, Department of Clinical Laboratories, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Millennium Initiative for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
- Clinical Laboratories Network, Red de Salud UC-CHRISTUS, Santiago, Chile
| | - Andres Opazo-Capurro
- Millennium Initiative for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Joyce To
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
| | - Patricia Garcia
- Laboratory of Microbiology, Department of Clinical Laboratories, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Millennium Initiative for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
- Clinical Laboratories Network, Red de Salud UC-CHRISTUS, Santiago, Chile
| | - Mehrad Hamidian
- Australian Institute for Microbiology and Infection, University of Technology Sydney, Ultimo, New South Wales, Australia
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Cahill SM, Hall RM, Kenyon JJ. An update to the database for Acinetobacter baumannii capsular polysaccharide locus typing extends the extensive and diverse repertoire of genes found at and outside the K locus. Microb Genom 2022; 8. [PMID: 36214673 DOI: 10.1099/mgen.0.000878] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Several novel non-antibiotic therapeutics for the critical priority bacterial pathogen, Acinetobacter baumannii, rely on specificity to the cell-surface capsular polysaccharide (CPS). Hence, prediction of CPS type deduced from genes in whole genome sequence data underpins the development and application of these therapies. In this study, we provide a comprehensive update to the A. baumannii K locus reference sequence database for CPS typing (available in Kaptive v. 2.0.1) to include 145 new KL, providing a total of 237 KL reference sequences. The database was also reconfigured for compatibility with the updated Kaptive v. 2.0.0 code that enables prediction of 'K type' from special logic parameters defined by detected combinations of KL and additional genes outside the K locus. Validation of the database against 8994 publicly available A. baumannii genome assemblies from NCBI databases identified the specific KL in 73.45 % of genomes with perfect, very high or high confidence. Poor sequence quality or the presence of insertion sequences were the main reasons for lower confidence levels. Overall, 17 KL were overrepresented in available genomes, with KL2 the most common followed by the related KL3 and KL22. Substantial variation in gene content of the central portion of the K locus, that usually includes genes specific to the CPS type, included 34 distinct groups of genes for synthesis of various complex sugars and >400 genes for forming linkages between sugars or adding non-sugar substituents. A repertoire of 681 gene types were found across the 237 KL, with 88.4 % found in <5 % of KL.
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Affiliation(s)
- Sarah M Cahill
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Ruth M Hall
- School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia
| | - Johanna J Kenyon
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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Tian C, Xing M, Zhao Y, Fan X, Bai Y, Fu L, Wang S. Whole genome sequencing of OXA-232-producing wzi93-KL112-O1 carbapenem-resistant Klebsiella pneumoniae in human bloodstream infection co-harboring chromosomal ISEcp1-based blaCTX-M-15 and one rmpA2-associated virulence plasmid. Front Cell Infect Microbiol 2022; 12:984479. [PMID: 36250056 PMCID: PMC9560801 DOI: 10.3389/fcimb.2022.984479] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022] Open
Abstract
Objectives To characterize one OXA-232-producing wzi93-KL112-O1 carbapenem-resistant Klebsiella pneumoniae (CRKP) co-harboring chromosomal blaCTX-M-15 and one rmpA2-associated virulence plasmid. Methods Minimum inhibitory concentrations (MICs) were measured via broth microdilution method. Conjugation, chemical transformation, string test and Galleria mellonella infection model experiments were also conducted. Whole-genome sequencing (WGS) was performed on the Illumina and Nanopore platforms. Antimicrobial resistance determinants were identified using ABRicate program with ResFinder database. Insertion sequences (ISs) were identified using ISfinder. Bacterial virulence factors were identified using virulence factor database (VFDB). Wzi, capsular polysaccharide (KL) and lipoolygosaccharide (OCL) were analyzed using Kleborate with Kaptive. Phylogenetic analysis of 109 ST15 K. pneumoniae strains was performed using core genome multilocus sequence typing (cgMLST) on the Ridom SeqSphere+ server. MLST, replicons type, SNP strategies and another cgMLST analysis for 45 OXA-232-producing K. pneumoniae strains were further conducted using BacWGSTdb server. Results K. pneumoniae KPTCM strain belongs to ST15 with wzi93, KL112 and O1. It possessed a multidrug-resistant (MDR) profile and was resistant to carbapenems (meropenem and ertapenem), ciprofloxacin and amikacin. Virulence assays demonstrated KPTCM strain possesses a low virulence phenotype. WGS revealed it contained one circular chromosome and nine plasmids. The carbapenemase-encoding gene blaOXA-232 was located in a 6141-bp ColKP3-type non-conjugative plasmid and flanked by ΔISEcp1 and ΔlysR-ΔereA. Interestingly, blaCTX-M-15 was located in the chromosome mediated by ISEcp1-based transposon Tn2012. Importantly, it harbored a rmpA2-associated pLVPK-like virulence plasmid with iutA-iucABCD gene cluster and one IS26-mediated MDR fusion plasmid according to 8-bp (AGCTGCAC or GGCCTTTG) target site duplications (TSD). Based on the cgMLST and SNP analysis, data showed OXA-232-producing ST15 K. pneumoniae isolates were mainly isolated from China and have evolved in recent years. Conclusions Early detection of CRKP strains carrying chromosomal blaCTX-M-15, OXA-232 carbapenemase and pLVPK-like virulence plasmid is recommended to avoid the extensive spread of this high-risk clone.
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Affiliation(s)
- Chongmei Tian
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, China
| | - Mengyu Xing
- Department of Pharmacy, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yaping Zhao
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, China
| | - Xueyu Fan
- Department of Clinical Laboratory, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
| | - Yongfeng Bai
- Department of Clinical Laboratory, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
| | - Liping Fu
- Department of Pharmacy, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, China
- *Correspondence: Siwei Wang, ; Liping Fu,
| | - Siwei Wang
- Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
- *Correspondence: Siwei Wang, ; Liping Fu,
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