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Megli CJ, Carlin SM, Giacobe EJ, Hillebrand GH, Hooven TA. Virulence and pathogenicity of group B Streptococcus: Virulence factors and their roles in perinatal infection. Virulence 2025; 16:2451173. [PMID: 39844743 PMCID: PMC11758947 DOI: 10.1080/21505594.2025.2451173] [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: 08/21/2024] [Revised: 12/02/2024] [Accepted: 01/05/2025] [Indexed: 01/24/2025] Open
Abstract
This review summarizes key virulence factors associated with group B Streptococcus (GBS), a significant pathogen particularly affecting pregnant women, fetuses, and infants. Beginning with an introduction to the historical transition of GBS from a zoonotic pathogen to a prominent cause of human infections, particularly in the perinatal period, the review describes major disease manifestations caused by GBS, including sepsis, meningitis, chorioamnionitis, pneumonia, and others, linking each to specific virulence mechanisms. A detailed exploration of the genetic basis for GBS pathogenicity follows, emphasizing the roles of capsules in pathogenesis and immune evasion. The paper also examines the molecular structures and functions of key GBS surface proteins, such as pili, serine-rich repeat proteins, and fibrinogen-binding proteins, which facilitate colonization and disease. Additionally, the review discusses the significance of environmental sensing and response systems, like the two-component systems, in adapting GBS to different host environments. We conclude by addressing current efforts in vaccine development, underscoring the need for effective prevention strategies against this pervasive pathogen.
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Affiliation(s)
- Christina J. Megli
- Department of Obstetrics and Gynecology, University of Pittsburgh School of Medicine, Pittsburgh, USA
- Magee-Womens Research Institute, UPMC Medical Center, Pittsburgh, USA
| | - Sophia M. Carlin
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Elizabeth J. Giacobe
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Gideon H. Hillebrand
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
| | - Thomas A. Hooven
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, USA
- R.K. Mellon Institute for Pediatric Research, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, USA
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2
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Assane IM, de Oliveira Neto RR, de Abreu Reis Ferreira D, do Vale Oliveira A, Hashimoto DT, Pilarski F. Genetic diversity, virulence genes, antimicrobial resistance genes, and antimicrobial susceptibility of group B Streptococcus (GBS) associated with mass mortalities of cultured Nile tilapia in Brazil. Microb Pathog 2025; 205:107664. [PMID: 40324602 DOI: 10.1016/j.micpath.2025.107664] [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: 03/30/2024] [Revised: 05/01/2025] [Accepted: 05/02/2025] [Indexed: 05/07/2025]
Abstract
Streptococcus agalactiae, group B Streptococcus (GBS), stands as the primary bacterial pathogen affecting cultured Nile tilapia (Oreochromis niloticus) globally, leading to significant mortalities throughout the farming cycle. This study investigated the genetic diversity, virulence and antibiotic resistance (AMR) genes presence, and antimicrobial susceptibility of 72 GBS strains associated with mass mortalities of Nile tilapia in Brazil. Isolate identity was confirmed by morphological, biochemical and molecular analyses. Capsular serotype, multi-locus sequence typing (MLST) allelic profiles and putative pathogenic factors were determined through polymerase chain reaction (PCR), gel electrophoresis, DNA sequencing and molecular analyses. The presence of AMR genes and antimicrobial susceptibility to florfenicol (FFC), oxytetracycline (OTC), thiamphenicol (TAP) and their combination were evaluated by PCR, followed by gel electrophoresis, and broth microdilution antimicrobial susceptibility testing, respectively. All clinical isolates studied were confirmed to be GBS, one from serotype III (IA2201) and 71 from serotype Ib, suggesting that serotype Ib was the most prevalent strain between 2011 and 2016 in the southern region of Brazil. Eight different allelic profiles were identified for the first time, with adhP-52, pheS-2, atr-31, glnA-4, sdhA-2, tkt-19 being the most predominant. Between one (glcK) and three (adhP and glnA) alleles were present at each locus. All strains, except IA2201, were negative for the glcK gene. Hyaluronate lyase (hlyB) and the GBS immunogenic bacterial adhesin A (bibA) were detected in all strains, except for 18P, which was negative for hlyB. On the other hand, α and β antigens of the C protein were only detected in IA2201. All antimicrobials showed high minimum inhibitory concentration (MIC ≥ 16 μg/mL) values against several strains with negative results for resistance genes. The combination involving OTC and TAP or FFC is a likely candidate for improving the treatment of streptococcosis caused by GBS using combination therapy, even for strains showing phenotypic and genotypic resistance to OTC. This study provides important data on pathogenic GBS genetic diversity, the presence of virulence and antimicrobial resistance genes and antimicrobial susceptibility, which may be useful in the development of effective vaccines and therapeutic strategies for the prevention and control of streptococcosis in aquaculture farms.
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Affiliation(s)
- Inácio Mateus Assane
- Laboratory of Microbiology and Parasitology of Aquatic Organisms, São Paulo State University (Unesp), Aquaculture Center of Unesp, Jaboticabal, SP, Brazil, 14884-900; Animal Health Laboratory, Faculty of Agricultural Sciences, Zambeze University (UniZambeze), Ulónguè, Tete 0713-02, Mozambique.
| | - Rubens Ricardo de Oliveira Neto
- São Paulo State University (Unesp), Aquaculture Center of Unesp, Laboratory of Aquaculture Genetics and Conservation, SP, Brazil, 14884-900
| | - Daniel de Abreu Reis Ferreira
- Graduate Program in Agricultural and Livestock Microbiology, São Paulo State University (UNESP), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil, 14870-00
| | - André do Vale Oliveira
- Laboratory of Microbiology and Parasitology of Aquatic Organisms, São Paulo State University (Unesp), Aquaculture Center of Unesp, Jaboticabal, SP, Brazil, 14884-900
| | - Diogo Teruo Hashimoto
- São Paulo State University (Unesp), Aquaculture Center of Unesp, Laboratory of Aquaculture Genetics and Conservation, SP, Brazil, 14884-900
| | - Fabiana Pilarski
- Laboratory of Microbiology and Parasitology of Aquatic Organisms, São Paulo State University (Unesp), Aquaculture Center of Unesp, Jaboticabal, SP, Brazil, 14884-900; Graduate Program in Agricultural and Livestock Microbiology, São Paulo State University (UNESP), School of Agricultural and Veterinarian Sciences, Jaboticabal, SP, Brazil, 14870-00
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3
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Ipe DS, Goh KG, Desai D, Ben-Zakour N, Sullivan MJ, Beatson SA, Ulett GC. Group B Streptococcus growth in human urine is associated with asymptomatic bacteriuria rather than urinary tract infection and is unaffected by iron sequestration. MICROBIOLOGY (READING, ENGLAND) 2025; 171:001533. [PMID: 39976609 PMCID: PMC11842879 DOI: 10.1099/mic.0.001533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Accepted: 01/27/2025] [Indexed: 02/23/2025]
Abstract
Group B Streptococcus (GBS) causes various infections in adults, including urinary tract infection (UTI) and asymptomatic bacteriuria (ABU). Some bacteria that cause ABU can utilize urine as a substrate for growth, which can promote asymptomatic colonization in the host. An analysis of diverse GBS isolates associated with ABU and UTI for growth in human urine has not been undertaken. Here, we examined a large collection of clinical urinary GBS isolates from individuals with acute UTI (n=62), and ABU with bacteriuria ≥104 c.f.u. ml-1 (n=206) or <104 c.f.u. ml-1 (n=90) for their ability to grow in human urine. Among all 358 GBS isolates analysed, 40 exhibited robust growth in urine in contrast to 25 that were unable to grow and non-culturable after incubation in urine. Growth phenotypes were disproportionately represented among the different groups of isolates, whereby robust growth was significantly more likely to be associated with high-grade ABU versus low-grade ABU or acute UTI (38/40 vs. 11/25; odds ratio 4.6, 95% CI, 1.5-14.8). Growth of bacteria in urine can depend on iron bioavailability, and we therefore performed growth assays using urine supplemented with 2,2-dipyridyl to chelate iron. In contrast to a control strain of ABU Escherichia coli, for which iron limitation significantly attenuated growth, iron sequestration had no significant attenuation effect on the growth of ABU GBS strain 834 in urine. Despite this finding, PCR confirmed the presence of several known growth-associated genes in GBS 834, including fhuD for iron uptake. We conclude that GBS adaptation for growth in human urine is more likely to be associated with high-grade ABU than acute UTI, and for GBS 834, this growth trait is not significantly constrained by conditions of iron sequestration.
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Affiliation(s)
- Deepak S. Ipe
- School of Pharmacy and Medical Sciences, Institute for Biomedicine and Glycomics, Griffith University, Gold Coast Campus, Gold Coast, QLD 4222, Australia
| | - Kelvin G.K. Goh
- School of Pharmacy and Medical Sciences, Institute for Biomedicine and Glycomics, Griffith University, Gold Coast Campus, Gold Coast, QLD 4222, Australia
| | - Devika Desai
- School of Pharmacy and Medical Sciences, Institute for Biomedicine and Glycomics, Griffith University, Gold Coast Campus, Gold Coast, QLD 4222, Australia
| | - Nouri Ben-Zakour
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Matthew J. Sullivan
- School of Pharmacy and Medical Sciences, Institute for Biomedicine and Glycomics, Griffith University, Gold Coast Campus, Gold Coast, QLD 4222, Australia
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Scott A. Beatson
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Glen C. Ulett
- School of Pharmacy and Medical Sciences, Institute for Biomedicine and Glycomics, Griffith University, Gold Coast Campus, Gold Coast, QLD 4222, Australia
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4
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Wang Y, Liu T, Sida Y, Zhu Y. Diversity and Evolution of the Mobilome Associated with Antibiotic Resistance Genes in Streptococcus anginosus. Microb Drug Resist 2025; 31:52-63. [PMID: 39837262 DOI: 10.1089/mdr.2024.0229] [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] [Indexed: 01/23/2025] Open
Abstract
Streptococcus anginosus is an important cause of pyogenic infections, bacteremia, and chronic maxillary sinusitis. Mobile genetic elements (MGEs) play a key role in lateral gene transfer, resulting in broad transfer of antibiotic resistance genes (ARGs). However, studies on ARG-associated MGEs in S. anginosus are still rare. To fill this gap, we used sequencing data from 11 clinical S. anginosus to characterize their mobilome diversity through comparative analysis. We found 47 well-characterized MGEs, including 23 putative integrative and conjugative elements (ICEs), 16 prophages/integrative mobilizable elements, and 8 composites. They were inserted into 16 positions, 4 of which were hot spots. A comprehensive analysis revealed that ARG-associated ICEs belong to four groups as follows: single serine integrases (ICESan49.2), tyrosine integrases (ICESan26.2), triple serine integrase ICEs (ICESan195.1), and a putative transposon integrase (ICESan49.1), all of which were similar to ICEs/transposons widely distributed among other streptococci. The eight composites were composed of multiple ICEs or transposons through successive accretion events (tandem or/and internal integration). In conclusion, we found that S. anginosus accumulates a variety of ARG-associated ICE/composites that may enable S. anginosus to serve as an ARG-associated MGE repository for other streptococci. The analysis of composites here provides a paradigm to further study mobilome evolution.
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Affiliation(s)
- Yingting Wang
- Department of Critical Care Medicine, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Taoran Liu
- Department of Critical Care Medicine, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yi Sida
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China
| | - Yuanting Zhu
- NHC Key Laboratory of Assisted Circulation, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
- Department of Cardiology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
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5
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Eren AM, Banfield JF. Modern microbiology: Embracing complexity through integration across scales. Cell 2024; 187:5151-5170. [PMID: 39303684 PMCID: PMC11450119 DOI: 10.1016/j.cell.2024.08.028] [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: 06/22/2024] [Revised: 08/14/2024] [Accepted: 08/14/2024] [Indexed: 09/22/2024]
Abstract
Microbes were the only form of life on Earth for most of its history, and they still account for the vast majority of life's diversity. They convert rocks to soil, produce much of the oxygen we breathe, remediate our sewage, and sustain agriculture. Microbes are vital to planetary health as they maintain biogeochemical cycles that produce and consume major greenhouse gases and support large food webs. Modern microbiologists analyze nucleic acids, proteins, and metabolites; leverage sophisticated genetic tools, software, and bioinformatic algorithms; and process and integrate complex and heterogeneous datasets so that microbial systems may be harnessed to address contemporary challenges in health, the environment, and basic science. Here, we consider an inevitably incomplete list of emergent themes in our discipline and highlight those that we recognize as the archetypes of its modern era that aim to address the most pressing problems of the 21st century.
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Affiliation(s)
- A Murat Eren
- Helmholtz Institute for Functional Marine Biodiversity, 26129 Oldenburg, Germany; Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany; Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany; Marine Biological Laboratory, Woods Hole, MA, USA; Max Planck Institute for Marine Microbiology, Bremen, Germany.
| | - Jillian F Banfield
- Department of Earth and Planetary Sciences, University of California, Berkeley, Berkeley, CA, USA; Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA; Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia; Department of Environmental Science Policy, and Management, University of California, Berkeley, Berkeley, CA, USA.
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6
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Kareem BO, Gazioglu O, Mueller Brown K, Habtom M, Glanville DG, Oggioni MR, Andrew PW, Ulijasz AT, Hiller NL, Yesilkaya H. Environmental and genetic regulation of Streptococcus pneumoniae galactose catabolic pathways. Nat Commun 2024; 15:5171. [PMID: 38886409 PMCID: PMC11183247 DOI: 10.1038/s41467-024-49619-w] [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: 10/27/2023] [Accepted: 06/10/2024] [Indexed: 06/20/2024] Open
Abstract
Efficient utilization of nutrients is crucial for microbial survival and virulence. The same nutrient may be utilized by multiple catabolic pathways, indicating that the physical and chemical environments for induction as well as their functional roles may differ. Here, we study the tagatose and Leloir pathways for galactose catabolism of the human pathogen Streptococcus pneumoniae. We show that galactose utilization potentiates pneumococcal virulence, the induction of galactose catabolic pathways is influenced differentially by the concentration of galactose and temperature, and sialic acid downregulates galactose catabolism. Furthermore, the genetic regulation and in vivo induction of each pathway differ, and both galactose catabolic pathways can be turned off with a galactose analogue in a substrate-specific manner, indicating that galactose catabolic pathways can be potential drug targets.
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Affiliation(s)
- Banaz O Kareem
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
- Department of Basic Medical Sciences, College of Medicine, University of Sulaimani, Sulaimani, Iraq
| | - Ozcan Gazioglu
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - Karina Mueller Brown
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Medhanie Habtom
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - David G Glanville
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - Marco R Oggioni
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
- Department of Pharmacy and Biotechnology, Bologna, Italy
| | - Peter W Andrew
- Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - Andrew T Ulijasz
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - N Luisa Hiller
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Hasan Yesilkaya
- Department of Respiratory Sciences, University of Leicester, Leicester, UK.
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7
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Chen XW, Wu JH, Liu YL, Munang’andu HM, Peng B. Fructose promotes ampicillin killing of antibiotic-resistant Streptococcus agalactiae. Virulence 2023; 14:2180938. [PMID: 36803528 PMCID: PMC9980678 DOI: 10.1080/21505594.2023.2180938] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Streptococcus agalactiae (GBS) is an important pathogenic bacteria that infected both aquatic animals and human beings, causing huge economic loss. The increasing cases of antibiotic-resistant GBS impose challenges to treat such infection by antibiotics. Thus, it is highly demanded for the approach to tackle antibiotic resistance in GBS. In this study, we adopt a metabolomic approach to identify the metabolic signature of ampicillin-resistant GBS (AR-GBS) that ampicillin is the routine choice to treat infection by GBS. We find glycolysis is significantly repressed in AR-GBS, and fructose is the crucial biomarker. Exogenous fructose not only reverses ampicillin resistance in AR-GBS but also in clinic isolates including methicillin-resistant Staphylococcus aureus (MRSA) and NDM-1 expressing Escherichia coli. The synergistic effect is confirmed in a zebrafish infection model. Furthermore, we demonstrate that the potentiation by fructose is dependent on glycolysis that enhances ampicillin uptake and the expression of penicillin-binding proteins, the ampicillin target. Our study demonstrates a novel approach to combat antibiotic resistance in GBS.
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Affiliation(s)
- Xuan-Wei Chen
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Higher Education Mega Center, Guangzhou, China,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jia-Han Wu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Higher Education Mega Center, Guangzhou, China
| | - Ying-Li Liu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Higher Education Mega Center, Guangzhou, China
| | | | - Bo Peng
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Higher Education Mega Center, Guangzhou, China,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China,CONTACT Bo Peng
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8
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Le Gallou B, Pastuszka A, Lemaire C, Mereghetti L, Lanotte P. Group B Streptococcus CRISPR1 Typing of Maternal, Fetal, and Neonatal Infectious Disease Isolates Highlights the Importance of CC1 in In Utero Fetal Death. Microbiol Spectr 2023; 11:e0522122. [PMID: 37341591 PMCID: PMC10434043 DOI: 10.1128/spectrum.05221-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 05/24/2023] [Indexed: 06/22/2023] Open
Abstract
We performed a descriptive analysis of group B Streptococcus (GBS) isolates responsible for maternal and fetal infectious diseases from 2004 to 2020 at the University Hospital of Tours, France. This represents 115 isolates, including 35 isolates responsible for early-onset disease (EOD), 48 isolates responsible for late-onset disease (LOD), and 32 isolates from maternal infections. Among the 32 isolates associated with maternal infection, 9 were isolated in the context of chorioamnionitis associated with in utero fetal death. Analysis of neonatal infection distribution over time highlighted the decrease in EOD since the early 2000s, while LOD incidence has remained relatively stable. All GBS isolates were analyzed by sequencing their CRISPR1 locus, which is an efficient way to determine the phylogenetic affiliation of strains, as it correlates with the lineages defined by multilocus sequence typing (MLST). Thus, the CRISPR1 typing method allowed us to assign a clonal complex (CC) to all isolates; among these isolates, CC17 was predominant (60/115, 52%), and the other main CCs, such as CC1 (19/115, 17%), CC10 (9/115, 8%), CC19 (8/115, 7%), and CC23 (15/115, 13%), were also identified. As expected, CC17 isolates (39/48, 81.3%) represented the majority of LOD isolates. Unexpectedly, we found mainly CC1 isolates (6/9) and no CC17 isolates that were responsible for in utero fetal death. Such a result highlights the possibility of a particular role of this CC in in utero infection, and further investigations should be conducted on a larger group of GBS isolated in a context of in utero fetal death. IMPORTANCE Group B Streptococcus is the leading bacterium responsible for maternal and neonatal infections worldwide, also involved in preterm birth, stillbirth, and fetal death. In this study, we determined the clonal complex of all GBS isolates responsible for neonatal diseases (early- and late-onset diseases) and maternal invasive infections, including chorioamnionitis associated with in utero fetal death. All GBS was isolated at the University Hospital of Tours from 2004 to 2020. We described the local group B Streptococcus epidemiology, which confirmed national and international data concerning neonatal disease incidence and clonal complex distribution. Indeed, neonatal diseases are mainly characterized by CC17 isolates, especially in late-onset disease. Interestingly, we identified mainly CC1 isolates responsible for in utero fetal death. CC1 could have a particular role in this context, and such a result should be confirmed on a larger group of GBS isolated from in utero fetal death.
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Affiliation(s)
- Brice Le Gallou
- Université de Tours, INRAE, Infectiologie et Santé Publique, BRMF, Tours, France
- Service de Bactériologie-Virologie, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | - Adeline Pastuszka
- Université de Tours, INRAE, Infectiologie et Santé Publique, BRMF, Tours, France
- Service de Bactériologie-Virologie, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | - Coralie Lemaire
- Université de Tours, INRAE, Infectiologie et Santé Publique, BRMF, Tours, France
- Service de Bactériologie-Virologie, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | - Laurent Mereghetti
- Université de Tours, INRAE, Infectiologie et Santé Publique, BRMF, Tours, France
- Service de Bactériologie-Virologie, Centre Hospitalier Régional Universitaire de Tours, Tours, France
| | - Philippe Lanotte
- Université de Tours, INRAE, Infectiologie et Santé Publique, BRMF, Tours, France
- Service de Bactériologie-Virologie, Centre Hospitalier Régional Universitaire de Tours, Tours, France
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9
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Spencer BL, Job AM, Robertson CM, Hameed ZA, Serchejian C, Wiafe-Kwakye CS, Mendonça JC, Apolonio MA, Nagao PE, Neely MN, Korotkova N, Korotkov KV, Patras KA, Doran KS. Heterogeneity of the group B streptococcal type VII secretion system and influence on colonization of the female genital tract. Mol Microbiol 2023; 120:258-275. [PMID: 37357823 PMCID: PMC10527989 DOI: 10.1111/mmi.15115] [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: 01/25/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 06/27/2023]
Abstract
Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B Streptococcus (GBS), a leading cause of infection in newborns and immunocompromised adults. GBS T7SS comprises four subtypes based on variation in the C-terminus of EssC and the repertoire of downstream effectors; however, the intraspecies diversity of GBS T7SS and impact on GBS-host interactions remains unknown. Bioinformatic analysis indicates that GBS T7SS loci encode subtype-specific putative effectors, which have low interspecies and inter-subtype homology but contain similar domains/motifs and therefore may serve similar functions. We further identify orphaned GBS WXG100 proteins. Functionally, we show that GBS T7SS subtype I and III strains secrete EsxA in vitro and that in subtype I strain CJB111, esxA1 appears to be differentially transcribed from the T7SS operon. Furthermore, we observe subtype-specific effects of GBS T7SS on host colonization, as CJB111 subtype I but not CNCTC 10/84 subtype III T7SS promotes GBS vaginal colonization. Finally, we observe that T7SS subtypes I and II are the predominant subtypes in clinical GBS isolates. This study highlights the potential impact of T7SS heterogeneity on host-GBS interactions.
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Affiliation(s)
- Brady L. Spencer
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
| | - Alyx M. Job
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
| | - Clare M. Robertson
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Zainab A. Hameed
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Camille Serchejian
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | | | - Jéssica C. Mendonça
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
- Rio de Janeiro State University, Roberto Alcântara Gomes Biology Institute, Rio de Janeiro, RJ, Brazil
| | - Morgan A. Apolonio
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
- National Summer Undergraduate Research Program, University of Arizona, Tucson, AZ, USA
| | - Prescilla E. Nagao
- Rio de Janeiro State University, Roberto Alcântara Gomes Biology Institute, Rio de Janeiro, RJ, Brazil
| | - Melody N. Neely
- University of Maine, Molecular & Biomedical Sciences, Orono, ME, USA
| | - Natalia Korotkova
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, USA
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA
| | - Konstantin V. Korotkov
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA
| | - Kathryn A. Patras
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
- Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX, USA
| | - Kelly S. Doran
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
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10
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Schindler Y, Rahav G, Nissan I, Valenci G, Ravins M, Hanski E, Ment D, Tekes-Manova D, Maor Y. Type VII secretion system and its effect on group B Streptococcus virulence in isolates obtained from newborns with early onset disease and colonized pregnant women. Front Cell Infect Microbiol 2023; 13:1168530. [PMID: 37545859 PMCID: PMC10400891 DOI: 10.3389/fcimb.2023.1168530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 07/03/2023] [Indexed: 08/08/2023] Open
Abstract
Introduction GBS may cause a devastating disease in newborns. In early onset disease of the newborn the bacteria are acquired from the colonized mother during delivery. We characterized type VII secretion system (T7SS), exporting small proteins of the WXG100 superfamily, in group B Streptococci (GBS) isolates from pregnant colonized women and newborns with early onset disease (EOD) to better understand T7SS contribution to virulence in these different clinical scenarios. Methods GBS genomes [N=33, 17 EOD isolates (serotype III/ST17) and 16 colonizing isolates (12 serotype VI/ST1, one serotype VI/ST19, one serotype VI/ST6, and two serotype 3/ST19)] were analyzed for presence of T7SS genes and genes encoding WXG100 proteins. We also perform bioinformatic analysis. Galleria mellonella larvae were used to compare virulence between colonizing, EOD, and mutant EOD isolates. The EOD isolate number 118659 (III/ST17) was used for knocking out the essC gene encoding a membrane-bound ATPase, considered the driver of T7SS. Results Most GBS T7SS loci encoded core component genes: essC, membrane-embedded proteins (essA; essB), modulators of T7SS activity (esaA; esaB; esaC) and effectors: [esxA (SAG1039); esxB (SAG1030)].Bioinformatic analysis indicated that based on sequence type (ST) the clinicalGBS isolates encode at least three distinct subtypes of T7SS machinery. In all ST1isolates we identified two copies of esxA gene (encoding putative WXG100proteins), when only 23.5% of the ST17 isolates harbored the esxA gene. Five ST17isolates encoded two copies of the essC gene. Orphaned WXG100 molecule(SAG0230), distinct from T7SS locus, were found in all tested strains, except inST17 strains where the locus was found in only 23.5% of the isolates. In ST6 andST19 isolates most of the structure T7SS genes were missing. EOD isolates demonstrated enhanced virulence in G. mellonella modelcompared to colonizing isolates. The 118659DessC strain was attenuated in itskilling ability, and the larvae were more effective in eradicating 118659DessC. Conclusions We demonstrated that T7SS plays a role during infection. Knocking out the essC gene, considered the driver of T7SS, decreased the virulence of ST17 responsible for EOD, causing them to be less virulent comparable to the virulence observed in colonizing isolates.
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Affiliation(s)
- Yulia Schindler
- Microbiology Laboratory, Mayanei Hayeshua Medical Center, Bney Brak, Israel
- The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Galia Rahav
- The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Infectious Disease Unit, Sheba Medical Center, Ramat-Gan, Israel
| | - Israel Nissan
- Infectious Disease Unit, Sheba Medical Center, Ramat-Gan, Israel
- National Public Health Laboratory, Ministry of Health (Israel), Tel-Aviv, Israel
| | - Gal Valenci
- National Public Health Laboratory, Ministry of Health (Israel), Tel-Aviv, Israel
| | - Miriam Ravins
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research, Israel-Canada (IMRIC), Faculty of Medicine, Jerusalem, Israel
| | - Emanuel Hanski
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research, Israel-Canada (IMRIC), Faculty of Medicine, Jerusalem, Israel
| | - Dana Ment
- Department of Plant Pathology and Weed Research, Plant Protection Institute, Agricultural Research Organization, Volcani Institute, Rishon LeZion, Israel
| | - Dorit Tekes-Manova
- Microbiology Laboratory, Mayanei Hayeshua Medical Center, Bney Brak, Israel
| | - Yasmin Maor
- The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Infectious Disease Unit, Wolfson Medical Center, Holon, Israel
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11
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Gamma-Irradiated Non-Capsule Group B Streptococcus Promotes T-Cell Dependent Immunity and Provides a Cross-Protective Reaction. Pharmaceuticals (Basel) 2023. [DOI: 10.3390/ph16020321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Group B Streptococcus (GBS) is a Gram-positive bacterium commonly found in the genitourinary tract and is also a leading cause of neonatal sepsis and pneumonia. Despite the current antibiotic prophylaxis (IAP), the disease burdens of late-onset disease in newborns and non-pregnant adult infections are increasing. Recently, inactivation of the pathogens via gamma radiation has been proven to eliminate their replication ability but cause less damage to the antigenicity of the key epitopes. In this study, the non-capsule GBS strain was inactivated via radiation (Rad-GBS) or formalin (Che-GBS), and we further determined its immunogenicity and protective efficacy as vaccines. Notably, Rad-GBS was more immunogenic and gave rise to higher expression of costimulatory molecules in BMDCs in comparison with Che-GBS. Flow cytometric analysis revealed that Rad-GBS induced a stronger CD4+ IFN-γ+ and CD4+IL-17A+ population in mice. The protective efficacy was measured through challenge with the highly virulent strain CNCTC 10/84, and the adoptive transfer results further showed that the protective role is reversed by functionally neutralizing antibodies and T cells. Finally, cross-protection against challenges with prevalent serotypes of GBS was induced by Rad-GBS. The higher opsonophagocytic killing activity of sera against multiple serotypes was determined in sera from mice immunized with Rad-GBS. Overall, our results showed that the inactivated whole-cell encapsulated GBS could be an alternative strategy for universal vaccine development against invasive GBS infections.
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12
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Clonal Complex 12 Serotype Ib Streptococcus agalactiae Strain Causing Complicated Sepsis in Neonates: Clinical Features and Genetic Characteristics. Microbiol Spectr 2023; 11:e0377822. [PMID: 36475780 PMCID: PMC9927456 DOI: 10.1128/spectrum.03778-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Streptococcus agalactiae (group B Streptococcus [GBS]) is well known to cause serious diseases in infants. A serotype Ib GBS strain has recently emerged and become prevalent in Southeast Asia. We aimed to investigate the clinical and genetic characteristics of this strain. All neonates with invasive GBS diseases from a tertiary-level medical center in Taiwan between 2003 and 2020 were analyzed. The capsule serotyping, multilocus sequence typing, and antimicrobial resistance analyses were performed on all the invasive GBS isolates, and whole-genome sequencing (WGS) was performed specifically on the type Ib GBS strain. A total of 188 neonates with invasive GBS disease during the study period were identified. The type Ib GBS strain accounted for 7.4% (n = 14) of neonatal GBS invasive diseases. Almost all type Ib GBS isolates belonged to sequence type 12 (13/14, 92.9%) and clonal complex 12. Neonates with type Ib GBS disease had a significantly higher rate of complicated sepsis (10/14, 71.4%; P < 0.05) and sepsis-attributable mortality (6/14, 42.9%; P < 0.05). Additionally, type Ib GBS isolates had significantly higher rates of resistance to erythromycin and clindamycin (both 100%; P < 0.05) than other GBS serotypes. WGS revealed the presence of an ~75-kb integrative and conjugative element, ICESag37, comprising multiple antibiotic resistance and virulence genes, and PI-1 plus PI-2a were noted in all type Ib serotype 12 (ST12) GBS isolates; these isolates may be responsible for its high invasiveness and antimicrobial resistance rates. The genomic characteristics of the type Ib clonal complex 12 (CC12) GBS strain may account for the high illness severity associated with this strain and its antibiotic resistance. Continuous monitoring and advanced strategies to control the spread of type Ib CC12 GBS should be considered. IMPORTANCE A type Ib ST12 GBS strain is not a common isolate in neonatal invasive diseases and has been ignored for a long time. However, the recent literature and our data showed that such a GBS strain is associated with a significantly higher risk of severe sepsis, higher illness severity, and a significantly higher rate of sepsis-attributable mortality. This study found a novel gene cluster, including the presence of ICESag37 and specific pilus genes, carrying multiple antimicrobial resistance and virulence genes, which may be responsible for the clinical characteristics. Because of the higher mortality and severity of illness, we concluded that continuous monitoring of the type Ib ST12 GBS strain is warranted in the future.
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13
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Schindler Y, Rahav G, Nissan I, Treygerman O, Prajgrod G, Attia BZ, Raz R, Valenci GZ, Tekes-Manova D, Maor Y. Group B streptococcus virulence factors associated with different clinical syndromes: Asymptomatic carriage in pregnant women and early-onset disease in the newborn. Front Microbiol 2023; 14:1093288. [PMID: 36860481 PMCID: PMC9968972 DOI: 10.3389/fmicb.2023.1093288] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/23/2023] [Indexed: 02/15/2023] Open
Abstract
Background Group B streptococcus (GBS) harbors many virulence factors but there is limited data regarding their importance in colonization in pregnancy and early-onset disease (EOD) in the newborn. We hypothesized that colonization and EOD are associated with different distribution and expression of virulence factors. Methods We studied 36 GBS EOD and 234 GBS isolates collected during routine screening. Virulence genes (pilus-like structures-PI-1, PI-2a, PI-2b; rib and hvgA) presence and expression were identified by PCR and qRT-PCR. Whole genome sequencing (WGS) and comparative genomic analyses were used to compare coding sequences (CDSs) of colonizing and EOD isolates. Results Serotype III (ST17) was significantly associated with EOD and serotype VI (ST1) with colonization. hvgA and rib genes were more prevalent among EOD isolates (58.3 and 77.8%, respectively; p < 0.01). The pilus loci PI-2b and PI-2a were more prevalent among EOD isolates (61.1%, p < 0.01), while the pilus loci PI-2a and PI-1 among colonizing isolates (89.7 and 93.1% vs. 55.6 and 69.4%, p < 0.01). qRT PCR analysis revealed that hvgA was barely expressed in colonizing isolates, even though the gene was detected. Expression of the rib gene and PI-2b was two-fold higher in EOD isolates compared to colonizing isolates. Transcription of PI-2a was three-fold higher in colonizing isolates compared to EOD isolates. ST17 isolates (associated with EOD) had a smaller genome size compared ST1 and the genome was more conserved relative to the reference strain and ST17 isolates. In a multivariate logistic regression analysis virulence factors independently associated with EOD were serotype 3, and PI-1 and PI-2a was protective. Conclusion There was a significant difference in the distribution of hvg A, rib, and PI genes among EOD (serotype III/ST17) and colonizing (serotype VI/ST1) isolates suggesting an association between invasive disease and these virulence factors. Further study is needed to understand the contribution of these genes to GBS virulence.
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Affiliation(s)
- Yulia Schindler
- Laboratory of Microbiology, Mayanei Hayeshua Medical Center, Bnei Brak, Israel,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Galia Rahav
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel,Infectious Disease Unit, Sheba Medical Center, Tel HaShomer, Israel
| | - Israel Nissan
- Infectious Disease Unit, Sheba Medical Center, Tel HaShomer, Israel,National Public Health Laboratory, Ministry of Health, Tel Aviv, Israel
| | - Orit Treygerman
- Laboratory of Microbiology, Meuhedet Health Maintenance Organization, Lod, Israel
| | - George Prajgrod
- Laboratory of Microbiology, Meuhedet Health Maintenance Organization, Lod, Israel
| | | | - Ronit Raz
- Laboratory of Microbiology, Mayanei Hayeshua Medical Center, Bnei Brak, Israel
| | | | - Dorit Tekes-Manova
- Laboratory of Microbiology, Mayanei Hayeshua Medical Center, Bnei Brak, Israel
| | - Yasmin Maor
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel,Infectious Disease Unit, Wolfson Medical Center, Holon, Israel,*Correspondence: Yasmin Maor, ,
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14
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Spencer BL, Job AM, Robertson CM, Hameed ZA, Serchejian C, Wiafe-Kwakye CS, Mendonça JC, Apolonio MA, Nagao PE, Neely MN, Korotkova N, Korotkov KV, Patras KA, Doran KS. Heterogeneity of the group B streptococcal type VII secretion system and influence on colonization of the female genital tract. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.25.525443. [PMID: 36747681 PMCID: PMC9900821 DOI: 10.1101/2023.01.25.525443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B Streptococcus (GBS), a leading cause of infection in newborns and immunocompromised adults. GBS T7SS comprises four subtypes based on variation in the C-terminus of EssC and the repertoire of downstream effectors; however, the intra-species diversity of GBS T7SS and impact on GBS-host interactions remains unknown. Bioinformatic analysis indicates that GBS T7SS loci encode subtype-specific putative effectors, which have low inter-species and inter-subtype homology but contain similar domains/motifs and therefore may serve similar functions. We further identify orphaned GBS WXG100 proteins. Functionally, we show that GBS T7SS subtype I and III strains secrete EsxA in vitro and that in subtype I strain CJB111, esxA1 appears to be differentially transcribed from the T7SS operon. Further, we observe subtype-specific effects of GBS T7SS on host colonization, as subtype I but not subtype III T7SS promotes GBS vaginal persistence. Finally, we observe that T7SS subtypes I and II are the predominant subtypes in clinical GBS isolates. This study highlights the potential impact of T7SS heterogeneity on host-GBS interactions.
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Affiliation(s)
- Brady L. Spencer
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
| | - Alyx M. Job
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
| | - Clare M. Robertson
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Zainab A. Hameed
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Camille Serchejian
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | | | - Jéssica C. Mendonça
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
- Rio de Janeiro State University, Roberto Alcantara Gomes Biology Institute, Rio de Janeiro, RJ, Brazil
| | - Morgan A. Apolonio
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
- National Summer Undergraduate Research Program, University of Arizona, Tucson, AZ, USA
| | - Prescilla E. Nagao
- Rio de Janeiro State University, Roberto Alcantara Gomes Biology Institute, Rio de Janeiro, RJ, Brazil
| | - Melody N. Neely
- University of Maine, Molecular & Biomedical Sciences, Orono, ME, USA
| | - Natalia Korotkova
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky, Lexington, KY, USA
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA
| | - Konstantin V. Korotkov
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA
| | - Kathryn A. Patras
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
- Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX, USA
| | - Kelly S. Doran
- University of Colorado-Anschutz, Department of Immunology and Microbiology, Aurora, CO, USA
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15
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Wang J, Zhang Y, Lin M, Bao J, Wang G, Dong R, Zou P, Chen Y, Li N, Zhang T, Su Z, Pan X. Maternal colonization with group B Streptococcus and antibiotic resistance in China: systematic review and meta-analyses. Ann Clin Microbiol Antimicrob 2023; 22:5. [PMID: 36639677 PMCID: PMC9837753 DOI: 10.1186/s12941-023-00553-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 01/03/2023] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Maternal rectovaginal colonization with group B Streptococcus (GBS) or Streptococcus agalactiae is the most common pathway for this disease during the perinatal period. This meta-analysis aimed to summarize existing data regarding maternal colonization, serotype profiles, and antibiotic resistance in China. METHODS Systematic literature reviews were conducted after searching 6 databases. Meta-analysis was applied to analyze colonization rate, serotype, and antimicrobial susceptibility of GBS clinical isolates in different regions of China. Summary estimates are presented using tables, funnel plots, forest plots, histograms, violin plots, and line plots. RESULTS The dataset regarding colonization included 52 articles and 195 303 pregnant women. Our estimate for maternal GBS colonization in China was 8.1% (95% confidence interval [CI] 7.2%-8.9%). Serotypes Ia, Ib, III, and V account for 95.9% of identified isolates. Serotype III, which is frequently associated with the hypervirulent clonal complex, accounts for 46.4%. Among the maternal GBS isolates using multilocus sequence typing (MLST), ST19 (25.7%, 289/1126) and ST10 (25.1%, 283/1126) were most common, followed by ST12 (12.4%, 140/1126), ST17 (4.8%, 54/1126), and ST651 (3.7%, 42/1126). GBS was highly resistant to tetracycline (75.1% [95% CI 74.0-76.3%]) and erythromycin (65.4% [95% CI 64.5-66.3%]) and generally susceptible to penicillin, ampicillin, vancomycin, ceftriaxone, and linezolid. Resistance rates of GBS to clindamycin and levofloxacin varied greatly (1.0-99.2% and 10.3-72.9%, respectively). A summary analysis of the bacterial drug resistance reports released by the China Antimicrobial Resistance Surveillance System (CARSS) in the past 5 years showed that the drug resistance rate of GBS to erythromycin, clindamycin, and levofloxacin decreased slowly from 2018 to 2020. However, the resistance rates of GBS to all 3 antibiotics increased slightly in 2021. CONCLUSIONS The overall colonization rate in China was much lower than the global colonization rate (17.4%). Consistent with many original and review reports in other parts of the world, GBS was highly resistant to tetracycline. However, the resistance of GBS isolates in China to erythromycin and clindamycin was greater than in other countries. This paper provides important epidemiological information, to assist with prevention and treatment of GBS colonization in these women.
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Affiliation(s)
- Jing Wang
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Yan Zhang
- Baoding No. 1 Hospital of TCM, Baoding, Hebei China
| | - Miao Lin
- grid.260474.30000 0001 0089 5711College of Life Sciences, Nanjing Normal University, Nanjing, Jiangsu China ,Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, No. 293 Zhongshan East Road, Nanjing, Jiangsu China
| | - Junfeng Bao
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Gaoying Wang
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Ruirui Dong
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Ping Zou
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Yuejuan Chen
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Na Li
- grid.258151.a0000 0001 0708 1323Women’s Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu China
| | - Ting Zhang
- Women's Hospital of Jiangnan University, No. 48, Huaishu Lane, Wuxi, Jiangsu, China.
| | - Zhaoliang Su
- School of Medicine, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, Jiangsu, China.
| | - Xiuzhen Pan
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, No. 293 Zhongshan East Road, Nanjing, Jiangsu, China.
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16
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Comparative genome analysis of Streptococcus strains to identify virulent genes causing neonatal meningitis. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2023; 107:105398. [PMID: 36572056 DOI: 10.1016/j.meegid.2022.105398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/19/2022] [Accepted: 12/22/2022] [Indexed: 12/25/2022]
Abstract
AIM To determine Streptococcus agalactiae genes responsible for causing neonatal meningitis. BACKGROUND Streptococcus agalactiae strain 2603 V/R is causative agent of neonatal meningitis, maternal infection and sepsis in young children. World health organisation reported high burden of new born death caused by this bacterium. Streptococcus agalactiae colonizing epithelial cells of vagina and endothelial cells have high resistance to available antibiotic drugs which makes it essential to determine new drug targets. OBJECTIVES To compare the genome of selected strain with the non-pathogenic strains of streptococcus and identify the virulent and antibiotic resistant genes for adaptation in host environment. METHOD The whole genome of human pathogen Streptococcus agalactiae strain 2603 V/R was analysed and compared with Streptococcus dysgalactiae strains using visualization and annotation tools. Genomic islands, mobile genetic elements, virulent and resistant genes were studied. RESULTS Genetically pathogenic strain is most similar to Streptococcus dysgalactiae subsp. equisimilis strain NCTC 7136. Comparative analysis revealed the importance of capsular polysaccharides and surface proteins responsible for avoiding immune system attachment to host epithelial cells and virulent behaviour. High number of genes coding for antibiotics resistance may provide a competitive advantage for survival of pathogenic Streptococcus agalactiae strain 2603 V/R in its niche. CONCLUSIONS The comparative analysis of pathogenic strain Streptococcus agalactiae with non-pathogenic strains of Streptococcus dysgalactiae provided new insights in pathogenicity that could aid in recognization for new regions and genes for development of new drug development strategies considering presence of high number of resistance genes.
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17
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Yesilkaya H, Oggioni MR, Andrew PW. Streptococcus pneumoniae: 'captain of the men of death' and financial burden. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36748691 DOI: 10.1099/mic.0.001275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Streptococcus pneumoniae may inhabit the upper respiratory tract of humans without causing harm but it also causes diseases with high morbidity and mortality. It has excellent adaptive capabilities thanks to its ability to shuffle its genetic content by acquiring and incorporating DNA from other bacteria and is highly competent for genetic transformation. Sugar sensing, cleavage and transport ensure its fitness and survival in the host, and intracellular survival in macrophages has been linked to virulence. The polysaccharide capsule and toxin pneumolysin are the most important virulence determinants. Polysaccharide-based vaccines provide protection against the serotypes represented in vaccine formulations.
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Affiliation(s)
- Hasan Yesilkaya
- Department of Respiratory Sciences, University of Leicester, Leicester LE1 7RH, UK
| | - Marco R Oggioni
- Department of Genetics, University of Leicester, Leicester LE1 7RH, UK.,Dipartimento di Farmacia e Biotecnologie, University of Bologna, Bologna, Italy
| | - Peter W Andrew
- Department of Respiratory Sciences, University of Leicester, Leicester LE1 7RH, UK
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18
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Improved assessments of bulk milk microbiota composition via sample preparation and DNA extraction methods. PLoS One 2022; 17:e0267992. [PMID: 36107863 PMCID: PMC9477292 DOI: 10.1371/journal.pone.0267992] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 08/24/2022] [Indexed: 11/30/2022] Open
Abstract
Although bacterial detection by 16S rRNA gene amplicon DNA sequencing is a widely-applied technique, standardized methods for sample preparation and DNA extraction are needed to ensure accuracy, reproducibility, and scalability for automation. To develop these methods for bovine bulk milk, we assembled and tested a bacterial cell mock community (BCMC) containing bacterial species commonly found in milk. The following protocol variations were examined:: BCMC enumeration (colony enumeration or microscopy), sample volume (200 μl to 30 ml), sample storage condition (frozen in PBS or 25% glycerol or exposure to freeze-thaw cycles), cell lysis method (bead-beating, vortex, enzymatic), and DNA extraction procedure (MagMAX Total, MagMAX CORE, and MagMAX Ultra 2.0, with and without either Proteinase K or RNase A). Cell enumeration by microscopy was more accurate for quantification of the BCMC contents. We found that least 10 mL (≥ 104 cells in high quality milk) is needed for reproducible bacterial detection by 16S rRNA gene amplicon DNA sequencing, whereas variations in storage conditions caused minor differences in the BCMC. For DNA extraction and purification, a mild lysis step (bead-beating for 10 s at 4 m/s or vortexing at 1800 rpm for 10 s) paired with the MagMAX Total kit and Proteinase K digestion provided the most accurate representation of the BCMC. Cell lysis procedures conferred the greatest changes to milk microbiota composition and these effects were confirmed to provide similar results for commercial milk samples. Overall, our systematic approach with the BCMC is broadly applicable to other milk, food, and environmental samples therefore recommended for improving accuracy of culture-independent, DNA sequence-based analyses of microbial composition in different habitats.
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Identification of Heat-Tolerant Genes in Non-Reference Sequences in Rice by Integrating Pan-Genome, Transcriptomics, and QTLs. Genes (Basel) 2022; 13:genes13081353. [PMID: 36011264 PMCID: PMC9407402 DOI: 10.3390/genes13081353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 07/22/2022] [Accepted: 07/26/2022] [Indexed: 01/04/2023] Open
Abstract
The availability of large-scale genomic data resources makes it very convenient to mine and analyze genes that are related to important agricultural traits in rice. Pan-genomes have been constructed to provide insight into the genome diversity and functionality of different plants, which can be used in genome-assisted crop improvement. Thus, a pan-genome comprising all genetic elements is crucial for comprehensive variation study among the heat-resistant and -susceptible rice varieties. In this study, a rice pan-genome was firstly constructed by using 45 heat-tolerant and 15 heat-sensitive rice varieties. A total of 38,998 pan-genome genes were identified, including 37,859 genes in the reference and 1141 in the non-reference contigs. Genomic variation analysis demonstrated that a total of 76,435 SNPs were detected and identified as the heat-tolerance-related SNPs, which were specifically present in the highly heat-resistant rice cultivars and located in the genic regions or within 2 kbp upstream and downstream of the genes. Meanwhile, 3214 upregulated and 2212 downregulated genes with heat stress tolerance-related SNPs were detected in one or multiple RNA-seq datasets of rice under heat stress, among which 24 were located in the non-reference contigs of the rice pan-genome. We then mapped the DEGs with heat stress tolerance-related SNPs to the heat stress-resistant QTL regions. A total of 1677 DEGs, including 990 upregulated and 687 downregulated genes, were mapped to the 46 heat stress-resistant QTL regions, in which 2 upregulated genes with heat stress tolerance-related SNPs were identified in the non-reference sequences. This pan-genome resource is an important step towards the effective and efficient genetic improvement of heat stress resistance in rice to help meet the rapidly growing needs for improved rice productivity under different environmental stresses. These findings provide further insight into the functional validation of a number of non-reference genes and, especially, the two genes identified in the heat stress-resistant QTLs in rice.
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Abstract
To investigate the presence and location of erm(T) in clinical Streptococcus suis isolates and explore the transmission ability and fitness cost of erm(T)-carrying mobile genetic elements among S. suis isolates, MICs were determined by broth microdilution. The presence of erm(T) in S. suis was detected by PCR. The genetic environment of erm(T) in S. suis was explored by whole-genome sequencing (WGS) analysis. Intraspecies and interspecies transmission were examined by electrotransformation. The fitness cost associated with the carriage of an erm(T)-harboring plasmid or an integrative and conjugative element (ICE) was examined by competition experiments. Of 237 nonduplicate strains, erm(T) was detected in 2 S. suis strains (SC262-ST954 and SC117-ST1314), with its location on a 5,125-bp plasmid in S. suis SC262 and on a 64,013-bp ICESsuSC117 in S. suis SC117, respectively. Both the erm(T)-carrying plasmid pSC262 and the ICESsuSC117 were transmissible by transformation. Plasmid pSC262 can replicate and express macrolide-lincosamide resistance in heterologous hosts, including S. aureus and S. pneumoniae. Both the erm(T)-carrying plasmid and the ICE posed a fitness cost to the host S. suis isolate. To the best of our knowledge, this is the first report of the macrolide-lincosamide-streptogramin B resistance gene erm(T) in S. suis. Its location on a plasmid or an ICE will aid in its transmission. The low detection rate of erm(T) gene among the S. suis population might be due to the fitness cost of the erm(T)-carrying plasmid and ICE. IMPORTANCE Macrolide and lincosamide resistance due to the presence of erm(T) have posed a challenge for the treatment of Gram-positive pathogens. Although the low detection rate of erm(T) gene among the S. suis population due to the fitness cost of the erm(T)-carrying plasmid and ICE, the presence of erm(T) in S. suis and its potential transmission to other Gram-positive pathogens will be of important significance.
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21
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Vaccines and Immunoinformatics for Vaccine Design. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1368:95-110. [DOI: 10.1007/978-981-16-8969-7_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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22
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Dobrut A, Brzychczy-Włoch M. Immunogenic Proteins of Group B Streptococcus-Potential Antigens in Immunodiagnostic Assay for GBS Detection. Pathogens 2021; 11:43. [PMID: 35055991 PMCID: PMC8778278 DOI: 10.3390/pathogens11010043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/29/2021] [Accepted: 12/29/2021] [Indexed: 12/21/2022] Open
Abstract
Streptococcus agalactiae (Group B Streptococcus, GBS) is an opportunistic pathogen, which asymptomatically colonizes the gastrointestinal and genitourinary tract of up to one third of healthy adults. Nevertheless, GBS carriage in pregnant women may lead to several health issues in newborns causing life threatening infection, such as sepsis, pneumonia or meningitis. Recommended GBS screening in pregnant women significantly reduced morbidity and mortality in infants. Nevertheless, intrapartum antibiotic prophylaxis, recommended following the detection of carriage or in case of lack of a carriage test result for pregnant women who demonstrate certain risk factors, led to the expansion of the adverse phenomenon of bacterial resistance to antibiotics. In our paper, we reviewed some immunogenic GBS proteins, i.e., Alp family proteins, β protein, Lmb, Sip, BibA, FsbA, ScpB, enolase, elongation factor Tu, IMPDH, and GroEL, which possess features characteristic of good candidates for immunodiagnostic assays for GBS carriage detection, such as immunoreactivity and specificity. We assume that they can be used as an alternative diagnostic method to the presently recommended bacteriological cultivation and MALDI.
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Affiliation(s)
| | - Monika Brzychczy-Włoch
- Department of Molecular Medical Microbiology, Faculty of Medicine, Medical College, Jagiellonian University, 31-121 Krakow, Poland;
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23
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Hsu JF, Tsai MH, Lin LC, Chu SM, Lai MY, Huang HR, Chiang MC, Yang PH, Lu JJ. Genomic Characterization of Serotype III/ST-17 Group B Streptococcus Strains with Antimicrobial Resistance Using Whole Genome Sequencing. Biomedicines 2021; 9:biomedicines9101477. [PMID: 34680594 PMCID: PMC8533585 DOI: 10.3390/biomedicines9101477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/11/2021] [Accepted: 10/12/2021] [Indexed: 12/25/2022] Open
Abstract
Background: Antibiotic-resistant type III/ST-17 Streptococcus agalactiae (group B Streptococcus, GBS) strain is predominant in neonatal invasive GBS diseases. We aimed to investigate the antibiotic resistance profiles and genetic characteristics of type III/ST-17 GBS strains. Methods: A total of 681 non-duplicate GBS isolates were typed (MLST, capsular types) and their antibiotic resistances were performed. Several molecular methods (WGS, PCR, sequencing and sequence analysis) were used to determine the genetic context of antibiotic resistant genes and pili genes. Results: The antibiotic resistant rates were significantly higher in type Ib (90.1%) and type III (71.1%) GBS isolates. WGS revealed that the loss of PI-1 genes and absence of ISSag5 was found in antibiotic-resistant III/ST-17 GBS isolates, which is replaced by a ~75-kb integrative and conjugative element, ICESag37, comprising multiple antibiotic resistance and virulence genes. Among 190 serotype III GBS isolates, the most common pilus island was PI-2b (58.4%) alone, which was found in 81.3% of the III/ST-17 GBS isolates. Loss of PI-1 and ISSag5 was significantly associated with antibiotic resistance (95.5% vs. 27.8%, p < 0.001). The presence of ICESag37 was found in 83.6% of all III/ST-17 GBS isolates and 99.1% (105/106) of the antibiotic-resistant III/ST-17 GBS isolates. Conclusions: Loss of PI-1 and ISSag5, which is replaced by ICESag37 carrying multiple antibiotic resistance genes, accounts for the high antibiotic resistance rate in III/ST-17 GBS isolates. The emerging clonal expansion of this hypervirulent strain with antibiotic resistance after acquisition of ICESag37 highlights the urgent need for continuous surveillance of GBS infections.
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Affiliation(s)
- Jen-Fu Hsu
- Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; (J.-F.H.); (S.-M.C.); (M.-Y.L.); (H.-R.H.); (M.-C.C.); (P.-H.Y.)
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Ming-Horng Tsai
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
- Division of Neonatology and Pediatric Hematology/Oncology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 638, Taiwan
| | - Lee-Chung Lin
- Department of Laboratory Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan;
| | - Shih-Ming Chu
- Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; (J.-F.H.); (S.-M.C.); (M.-Y.L.); (H.-R.H.); (M.-C.C.); (P.-H.Y.)
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Mei-Yin Lai
- Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; (J.-F.H.); (S.-M.C.); (M.-Y.L.); (H.-R.H.); (M.-C.C.); (P.-H.Y.)
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Hsuan-Rong Huang
- Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; (J.-F.H.); (S.-M.C.); (M.-Y.L.); (H.-R.H.); (M.-C.C.); (P.-H.Y.)
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Ming-Chou Chiang
- Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; (J.-F.H.); (S.-M.C.); (M.-Y.L.); (H.-R.H.); (M.-C.C.); (P.-H.Y.)
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Peng-Hong Yang
- Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan; (J.-F.H.); (S.-M.C.); (M.-Y.L.); (H.-R.H.); (M.-C.C.); (P.-H.Y.)
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Jang-Jih Lu
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
- Department of Laboratory Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan;
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan 333, Taiwan
- Correspondence: ; Tel.: +886-3-328-1200 (ext. 2554); Fax: +886-3-397-1827
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24
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Xiao X, Song T, Xiao X, Liu Y, Sun H, Guo Z, Liu X, Shao C, Li Q, Sun W. A qualitative and quantitative analysis of the human gingival crevicular fluid proteome and metaproteome. Proteomics 2021; 21:e2000321. [PMID: 34464030 DOI: 10.1002/pmic.202000321] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 08/02/2021] [Accepted: 08/20/2021] [Indexed: 11/08/2022]
Abstract
Gingival crevicular fluid (GCF) is an integral part of oral fluid that plays a special role in maintaining the structure of junctional epithelium and defending against bacterial infection. In this study, we comprehensively analysed the composition of the human GCF proteome and metaproteome simultaneously to obtain multidimensional information about GCF. A total of 3680 human proteins (2540 with at least two unique peptides) were identified in the normal GCF sample, and their functions were mainly associated with immune function and inflammation. Among these proteins, 1874 proteins could be quantified by the iBAQ algorithm, and their abundances spanned a dynamic range of six orders of magnitude. For the GCF metaproteome, a total of 3082 proteins and 69 genera were found. In addition, 16 genera were not identified by GCF metagenomic analysis. Compared to the saliva metaproteome, 32 genera were found to be in common. The protein quantitative analysis showed that the abundance of GCF metaproteome contributed to approximately 4.17% of the total GCF proteome. The top three most abundant genera were Fusobacterium, Corynebacterium, and Leptotrichia. The above data will be useful for future research on GCF-related diseases.
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Affiliation(s)
- Xiaoping Xiao
- Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.,Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Tingting Song
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing, China
| | - Xiaolian Xiao
- Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Yaoran Liu
- Department of Dentistry, Chinese Academy of Medical Sciences Peking Union Medical College Hospital, Beijing, China
| | - Haidan Sun
- Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Zhengguang Guo
- Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Xiaoyan Liu
- Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Chen Shao
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing, China
| | - Qian Li
- Department of Dentistry, Chinese Academy of Medical Sciences Peking Union Medical College Hospital, Beijing, China
| | - Wei Sun
- Core Facility of Instrument, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
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25
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Functional Insights into the High-Molecular-Mass Penicillin-Binding Proteins of Streptococcus agalactiae Revealed by Gene Deletion and Transposon Mutagenesis Analysis. J Bacteriol 2021; 203:e0023421. [PMID: 34124943 DOI: 10.1128/jb.00234-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
High-molecular-mass penicillin-binding proteins (PBPs) are enzymes that catalyze the biosynthesis of bacterial cell wall peptidoglycan. The Gram-positive bacterial pathogen Streptococcus agalactiae (group B streptococcus [GBS]) produces five high-molecular-mass PBPs, namely, PBP1A, PBP1B, PBP2A, PBP2B, and PBP2X. Among these, only PBP2X is essential for cell viability, whereas the other four PBPs are individually dispensable. The biological function of the four nonessential PBPs is poorly characterized in GBS. We deleted the pbp1a, pbp1b, pbp2a, and pbp2b genes individually from a genetically well-characterized serotype V GBS strain and studied the phenotypes of the four isogenic mutant strains. Compared to the wild-type parental strain, (i) none of the pbp isogenic mutant strains had a significant growth defect in Todd-Hewitt broth supplemented with 0.2% yeast extract (THY) rich medium, (ii) isogenic mutant Δpbp1a and Δpbp1b strains had significantly increased susceptibility to penicillin and ampicillin, and (iii) isogenic mutant Δpbp1a and Δpbp2b strains had significantly longer chain lengths. Using saturated transposon mutagenesis and transposon insertion site sequencing, we determined the genes essential for the viability of the wild-type GBS strain and each of the four isogenic pbp deletion mutant strains in THY rich medium. The pbp1a gene is essential for cell viability in the pbp2b deletion background. Reciprocally, pbp2b is essential in the pbp1a deletion background. Moreover, the gene encoding RodA, a peptidoglycan polymerase that works in conjunction with PBP2B, is also essential in the pbp1a deletion background. Together, our results suggest functional overlap between PBP1A and the PBP2B-RodA complex in GBS cell wall peptidoglycan biosynthesis. IMPORTANCE High-molecular-mass penicillin-binding proteins (HMM PBPs) are enzymes required for bacterial cell wall biosynthesis. Bacterial pathogen group B streptococcus (GBS) produces five distinct HMM PBPs. The biological functions of these proteins are not well characterized in GBS. In this study, we performed a comprehensive deletion analysis of genes encoding HMM PBPs in GBS. We found that deleting certain PBP-encoding genes altered bacterial susceptibility to beta-lactam antibiotics, cell morphology, and the essentiality of other enzymes involved in cell wall peptidoglycan synthesis. The results of our study shed new light on the biological functions of PBPs in GBS.
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26
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Shahin K, Veek T, Heckman TI, Littman E, Mukkatira K, Adkison M, Welch TJ, Imai DM, Pastenkos G, Camus A, Soto E. Isolation and characterization of Lactococcus garvieae from rainbow trout, Onchorhyncus mykiss, from California, USA. Transbound Emerg Dis 2021; 69:2326-2343. [PMID: 34328271 DOI: 10.1111/tbed.14250] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/17/2021] [Indexed: 11/26/2022]
Abstract
Lactococcus garvieae is an emergent bacterial pathogen of salmonid fish in North America that causes acute infections particularly at water temperatures above 15°C. During 2020, L. garvieae was detected in rainbow trout, Onchorhyncus mykiss, cultured in Southern California and the Eastern Sierras. Infected fish exhibited high mortalities and nonspecific clinical signs of lethargy, erratic swimming, dark skin pigmentation, and exophthalmia. Macroscopic changes included external and internal hemorrhages, mainly in the eyes, liver, coelomic fat, intestine, and brain. Histological examination revealed splenitis, branchitis, panophthalmitis, hepatitis, enteritis, and coelomitis, with variable degrees of tissue damage among evaluated fish. Pure colonies of L. garvieae were isolated from infected trout and specific PCR primers for L. garvieae confirmed the preliminary diagnosis. Multilocus sequence analysis showed that the strains recovered from diseased trout represent a novel genetic group. Isolates were able to form biofilms within 24 h that increased their resistance to disinfection by hydrogen peroxide. Laboratory challenge methods for inducing lactococcosis in steelhead trout, O. mykiss, were evaluated by intracoelomic injection with serial dilutions of L. garvieae. The median lethal dose 21 days post challenge was ∼20 colony-forming units/fish. Experimentally infected trout presented similar clinical signs, gross changes, and microscopic lesions as those with natural disease, fulfilling Koch's postulates and demonstrating the high virulence of the recovered strains.
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Affiliation(s)
- Khalid Shahin
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA.,Aquatic Animal Diseases Laboratory, Aquaculture Department, National Institute of Oceanography and Fisheries, Suez, Egypt
| | - Tresa Veek
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Taylor I Heckman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Eric Littman
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | | | - Mark Adkison
- California Department of Fish and Wildlife, Rancho Cordova, California, USA
| | - Timothy J Welch
- National Center for Cool and Coldwater Aquaculture, Kearneysville, West Virginia, USA
| | - Denise M Imai
- Comparative Pathology Laboratory, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Gabrielle Pastenkos
- Comparative Pathology Laboratory, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Alvin Camus
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Esteban Soto
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
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27
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Molecular Characteristics of IS 1216 Carrying Multidrug Resistance Gene Cluster in Serotype III/Sequence Type 19 Group B Streptococcus. mSphere 2021; 6:e0054321. [PMID: 34319128 PMCID: PMC8386385 DOI: 10.1128/msphere.00543-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus agalactiae is the leading cause of meningitis in newborns and a significant cause of invasive diseases in pregnant women and adults with underlying diseases. Antibiotic resistance against erythromycin and clindamycin in group B streptococcus (GBS) isolates has been increasing worldwide. GBS expresses the Srr1 and Srr2 proteins, which have important roles in bacterial infection. They have been investigated as novel vaccine candidates against GBS infection, with promising results. But a recent study detected non-srr1/2-expressing clinical isolates belonging to serotype III. Thus, we aimed to analyze the genotypes of non-srr1/2 GBS clinical isolates collected between 2013 and 2016 in South Korea. Forty-one (13.4%) of the 305 serotype III isolates were identified as non-srr1/2 strains, including sequence type 19 (ST19) (n = 16) and ST27 (n = 18) strains. The results of the comparative genomic analysis of the ST19/serotype III/non-srr1/2 strains further revealed four unique gene clusters. Site 4 in the srr1 gene locus was replaced by an lsa(E)-lnu(B)-aadK-aac-aph-aadE-carrying multidrug-resistant gene cluster flanked by two IS1216 transposases with 99% homology to the enterococcal plasmid pKUB3007-1. Despite the Srr1 and Srr2 deficiencies, which resulted in reduced fibrinogen binding, the adherence of non-srr1/2 strains to endothelial and epithelial cells was comparable to that of Srr1- or Srr2-expressing strains. Moreover, their virulence in mouse models of meningitis was not significantly affected. Furthermore, additional adhesin-encoding genes, including a gene encoding a BspA-like protein, which may contribute to colonization by non-srr1/2 strains, were identified via whole-genome analysis. Thus, our study provides important findings that can aid in the development of vaccines and antibiotics against GBS. IMPORTANCE Most previously isolated group B streptococcus (GBS) strains express either the Srr1 or Srr2 glycoprotein, which plays an important role in bacterial colonization and invasion. These glycoproteins are potential protein vaccine candidates. In this study, we first report GBS clinical isolates in which the srr1/2 gene was deleted or replaced with foreign genes. Despite Srr1/2 deficiency, in vitro adherence to mammalian cells and in vivo virulence in murine models were not affected, suggesting that the isolates might have another adherence mechanism that enhanced their virulence aside from Srr1/2-fibrinogen-mediated adherence. In addition, several non-srr1/2 isolates replaced the srr1/2 gene with the lnu(B) and lsa(E) antibiotic resistance genes flanked by IS1216, effectively causing multidrug resistance. Collectively, we believe that our study identifies the underlying genes responsible for the pathogenesis of new GBS serotype III. Furthermore, our study emphasizes the need for alternative antibiotics for patients who are allergic to β-lactams and for those who are pregnant.
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28
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He LY, Le YJ, Guo Z, Li S, Yang XY. The Role and Regulatory Network of the CiaRH Two-Component System in Streptococcal Species. Front Microbiol 2021; 12:693858. [PMID: 34335522 PMCID: PMC8317062 DOI: 10.3389/fmicb.2021.693858] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/15/2021] [Indexed: 11/13/2022] Open
Abstract
Pathogenic streptococcal species are responsible for a broad spectrum of human diseases ranging from non-invasive and localized infections to more aggressive and life-threatening diseases, which cause great economic losses worldwide. Streptococci possess a dozen two-component systems (TCSs) that play important roles in the response to different environmental changes and adjust the expression of multiple genes to successfully colonize and infect host cells. In this review, we discuss the progress in the study of a conserved TCS named CiaRH in pathogenic or opportunistic streptococci including Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus mutans, Streptococcus gordonii, Streptococcus sanguinis, and Streptococcus suis, focusing on the function and regulatory networks of CiaRH, which will provide a promising strategy for the exploration of novel antistreptococcal therapies. This review highlights the important role of CiaRH and provides an important basis for the development of antistreptococcal drugs and vaccines.
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Affiliation(s)
- Li-Yuan He
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, Department of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai, China
| | - Yao-Jin Le
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, Department of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai, China
| | - Zhong Guo
- Center for Biological Science and Technology, Beijing Normal University, Zhuhai, China
| | - Sha Li
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, Department of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai, China
| | - Xiao-Yan Yang
- Zhuhai Key Laboratory of Basic and Applied Research in Chinese Medicine, Department of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai, China
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29
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Qu LL, Ying YL, Yu RJ, Long YT. In situ food-borne pathogen sensors in a nanoconfined space by surface enhanced Raman scattering. Mikrochim Acta 2021; 188:201. [PMID: 34041602 PMCID: PMC8154335 DOI: 10.1007/s00604-021-04864-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/13/2021] [Indexed: 01/04/2023]
Abstract
The incidence of disease arising from food-borne pathogens is increasing continuously and has become a global public health problem. Rapid and accurate identification of food-borne pathogens is essential for adopting disease intervention strategies and controlling the spread of epidemics. Surface-enhanced Raman spectroscopy (SERS) has attracted increasing interest due to the attractive features including simplicity, rapid measurement, and high sensitivity. It can be used for rapid in situ sensing of single and multicomponent samples within the nanostructure-based confined space by providing molecular fingerprint information and has been demonstrated to be an effective detection strategy for pathogens. This article aims to review the application of SERS to the rapid sensing of food-borne pathogens in food matrices. The mechanisms and advantages of SERS, and detection strategies are briefly discussed. The latest progress on the use of SERS for rapid detection of food-borne bacteria and viruses is considered, including both the labeled and label-free detection strategies. In closing, according to the current situation regarding detection of food-borne pathogens, the review highlights the challenges faced by SERS and the prospects for new applications in food safety. In this review, the advances on the SERS detection of pathogens over the past decades have been reviewed, focusing on the improvements in sensitivity, reproducibility, specificity, and the performance of the SERS-based assay in complex analytical scenarios. ![]()
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Affiliation(s)
- Lu-Lu Qu
- School of Chemistry and Materials Science, Jiangsu Normal University, 221116, Xuzhou, People's Republic of China.
| | - Yi-Lun Ying
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, People's Republic of China
| | - Ru-Jia Yu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, People's Republic of China.
| | - Yi-Tao Long
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, People's Republic of China
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30
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Pastuszka A, Beauruelle C, Camiade E, Rousseau GM, Moineau S, Mereghetti L, Horvath P, Lanotte P. Functional Study of the Type II-A CRISPR-Cas System of Streptococcus agalactiae Hypervirulent Strains. CRISPR J 2021; 4:233-242. [PMID: 33876956 DOI: 10.1089/crispr.2020.0145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Nearly all strains of Streptococcus agalactiae, the leading cause of invasive infections in neonates, encode a type II-A clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system. Interestingly, S. agalactiae strains belonging to the hypervirulent Sequence Type 17 (ST17) contain significantly fewer spacers in their CRISPR locus than other lineages, which could be the result of a less functional CRISPR-Cas system. Here, we revealed one large deletion in the ST17 cas promoter region and we evaluated its impact on the transcription of cas genes as well as the functionalities of the CRISPR-Cas system. We demonstrated that Cas9 interference is functional and that the CRISPR-Cas system of ST17 strains can still acquire new spacers, despite the absence of a regular cas promoter. We demonstrated that a promoter sequence upstream of srn036, a small RNA partially overlapping the antisense tracrRNA, is responsible for the ST17 CRISPR-Cas adaptation and interference activities.
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Affiliation(s)
- Adeline Pastuszka
- ISP, Université de Tours, INRAE, Tours, France; Dangé-Saint-Romain, France.,Service de Bactériologie-Virologie-Hygiène Hospitalière, CHRU de Tours, Tours, France; Dangé-Saint-Romain, France
| | - Clémence Beauruelle
- Département de Bactériologie-Virologie, Hygiène Hospitalière et Parasitologie-Mycologie, Centre Hospitalier Régional Universitaire (CHRU) de Brest, Brest, France; Dangé-Saint-Romain, France.,Univ Brest, Inserm, EFS, UMR 1078, GGB, Brest, France; Dangé-Saint-Romain, France
| | - Emilie Camiade
- ISP, Université de Tours, INRAE, Tours, France; Dangé-Saint-Romain, France
| | - Geneviève M Rousseau
- Département de Biochimie, de Microbiologie, et de Bio-informatique, Faculté des Sciences et de Génie, Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec City, Canada; Dangé-Saint-Romain, France
| | - Sylvain Moineau
- Département de Biochimie, de Microbiologie, et de Bio-informatique, Faculté des Sciences et de Génie, Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Québec City, Canada; Dangé-Saint-Romain, France.,Félix d'Hérelle Reference Center for Bacterial Viruses, Université Laval, Québec City, Canada; and Dangé-Saint-Romain, France
| | - Laurent Mereghetti
- ISP, Université de Tours, INRAE, Tours, France; Dangé-Saint-Romain, France.,Service de Bactériologie-Virologie-Hygiène Hospitalière, CHRU de Tours, Tours, France; Dangé-Saint-Romain, France
| | | | - Philippe Lanotte
- ISP, Université de Tours, INRAE, Tours, France; Dangé-Saint-Romain, France.,Service de Bactériologie-Virologie-Hygiène Hospitalière, CHRU de Tours, Tours, France; Dangé-Saint-Romain, France
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Sharma A, Sanduja P, Anand A, Mahajan P, Guzman CA, Yadav P, Awasthi A, Hanski E, Dua M, Johri AK. Advanced strategies for development of vaccines against human bacterial pathogens. World J Microbiol Biotechnol 2021; 37:67. [PMID: 33748926 PMCID: PMC7982316 DOI: 10.1007/s11274-021-03021-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 02/17/2021] [Indexed: 12/18/2022]
Abstract
Infectious diseases are one of the main grounds of death and disabilities in human beings globally. Lack of effective treatment and immunization for many deadly infectious diseases and emerging drug resistance in pathogens underlines the need to either develop new vaccines or sufficiently improve the effectiveness of currently available drugs and vaccines. In this review, we discuss the application of advanced tools like bioinformatics, genomics, proteomics and associated techniques for a rational vaccine design.
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Affiliation(s)
- Abhinay Sharma
- School of Life Sciences, Jawaharlal Nehru University, Aruna Asaf Ali Marg, New Delhi, 110067, India
- Department of Vaccinology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research, Israel-Canada (IMRIC), Faculty of Medicine, The Hebrew University of Jerusalem, 9112102, Jerusalem, Israel
| | - Pooja Sanduja
- School of Life Sciences, Jawaharlal Nehru University, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Aparna Anand
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research, Israel-Canada (IMRIC), Faculty of Medicine, The Hebrew University of Jerusalem, 9112102, Jerusalem, Israel
| | - Pooja Mahajan
- School of Life Sciences, Jawaharlal Nehru University, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Carlos A Guzman
- Department of Vaccinology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
| | - Puja Yadav
- Department of Microbiology, Central University of Haryana, Mahendragarh, Harayana, India
| | - Amit Awasthi
- Translational Health Science and Technology Institute, Faridabad-Gurgaon Expressway, PO box #04, NCR Biotech Science Cluster, 3rd Milestone, Faridabad, Haryana, 121001, India
| | - Emanuel Hanski
- Department of Microbiology and Molecular Genetics, The Institute for Medical Research, Israel-Canada (IMRIC), Faculty of Medicine, The Hebrew University of Jerusalem, 9112102, Jerusalem, Israel
| | - Meenakshi Dua
- School of Environmental Sciences, Jawaharlal Nehru University, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Atul Kumar Johri
- School of Life Sciences, Jawaharlal Nehru University, Aruna Asaf Ali Marg, New Delhi, 110067, India.
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Yi S, Huang J, Hu X, Chen L, Dai X, Sun J, Liu P, Wang X, Wen J, Wang L. Nonconservative integration and diversity of a new family of integrative and conjugative elements associated with antibiotic resistance in zoonotic pathogen Streptococcus suis. Vet Microbiol 2021; 254:109009. [PMID: 33640677 DOI: 10.1016/j.vetmic.2021.109009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/02/2021] [Indexed: 11/24/2022]
Abstract
Macrolide and tetracycline resistance in streptococci is mainly caused by acquisition of integrative and conjugative elements (ICEs) of the ICESa2603 family carrying erm(B) and tet(O). But the characteristics about the transferability and physiological consequences of ICEs with triplet serine integrases are still rare. This study tested the transferability of ICESsuYZDH1_SSU0877, a novel erm(B)- and tet(O)-carrying ICESa2603 family-like ICE with triplet serine integrases, and evaluated the physiological consequences after ICE transferred and integrated into recipient. The prevalence of ICESsuYZDH1-like ICEs in S. suis was analyzed based on 1334 genomic sequences available in GenBank and examined in 330 clinical isolates in China. Nonconservative transfer was observed by integrating of ICESsuYZDH1 into SSU1797 gene besides the primary SSU0877 site. Imperfect direct repeats of 2-/4-nt (5'-TC-3'/5'-TCCC-3') and (5'-GC-3'/5'-TCCC-3') were observed at SSU0877 and SSU1797 sites, respectively. The transconjugant suffered a weak fitness cost with stunted growth and less competition with recipient strain. Successive passages indicate the ICESsuYZDH1 could be persist and endued stable resistant phenotype. Comprehensive analysis of the ICESsuYZDH1-like ICEs from both public genome database and our clinical isolates revealed the widespread and diversity of the ICEs by integration at the sites of SSU0877, SSU0468, SSU1262, and SSU1797. The ICESsuYZDH1-like ICEs could stably co-exist within the host chromosome at more than one attachment sites, which is probably mediated by the triplet serine integrases. Nonconservative integration and diversity of the ICESsuYZDH1 family of ICEs might have contributed to the evolution of ICEs and the dissemination of macrolide and tetracycline resistance in S. suis.
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Affiliation(s)
- Sida Yi
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Jinhu Huang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiao Hu
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA 50011, USA
| | - Li Chen
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Xingyang Dai
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Junjie Sun
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Peiyu Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiaoming Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Jia Wen
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Liping Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
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Genomic characteristics of Streptococcus agalactiae based on the pan-genome orthologous group analysis according to invasiveness and capsular genotype. J Infect Chemother 2021; 27:814-819. [PMID: 33526285 DOI: 10.1016/j.jiac.2021.01.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/10/2021] [Accepted: 01/13/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Following the construction of a bacterial pan-genome from the whole genome sequences on a web-based pipeline, all coding DNA sequences (CDSs) can be clustered into pan-genome orthologous groups (POGs), which is a similar approach to comparative genome hybridization on glass microscope slides. We aimed to clarify the genomic characteristics of Streptococcus agalactiae based on the POG analysis. METHODS Sixty-six S. agalactiae isolates obtained from invasive specimens (blood and cerebrospinal fluid) and non-invasive specimens (urine and vaginal discharge) between 2010 and 2017 in Korea were subjected to whole genome sequencing (WGS). Based on the WGS data, we conducted the POG analysis and constructed a phylogenetic tree along with capsular polysaccharide (CPS) genotyping. We compared the genomics of invasive vs. non-invasive isolates, as well as CPS III vs. non-CPS III genotypes. RESULTS Predicted pan- and core-genome sizes were 3416 and 1658 genes, respectively. We found four clusters consisting of CPS genotypes (III, VIII, Ib/VI, and Ia) in the phylogenetic tree. There were significant differences in two metabolic pathways specific to invasiveness, and in six metabolic pathways specific to CPS III type produced by CDSs. CONCLUSION Our observations reveal the pan- and core-genome sizes, four clusters of genomes distributed by CPS genotypes, and unique CDS features of S. agalactiae by comparative genomics in terms of invasiveness and CPS genotype.
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Gao K, Gao C, Huang L, Guan X, Ji W, Chang CY, McIver DJ, Deng Q, Zhong H, Xie Y, Deng L, Gao F, Zeng L, Liu H. Predominance of III/ST19 and Ib/ST10 Lineages With High Multidrug Resistance in Fluoroquinolone-Resistant Group B Streptococci Isolates in Which a New Integrative and Conjugative Element Was Identified. Front Microbiol 2021; 11:609526. [PMID: 33569045 PMCID: PMC7868321 DOI: 10.3389/fmicb.2020.609526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/11/2020] [Indexed: 01/31/2023] Open
Abstract
Fluoroquinolone (FQ)-resistant Group B Streptococcus (GBS) has been reported with considerable cross-resistance, worsening the crisis of multidrug-resistant (MDR) GBS in clinical settings. However, national epidemiological data on FQ-resistant GBS in mainland China have not been well-characterized. This study aimed to determine the prevalence of FQ resistance among GBS from neonatal invasive infections and maternal colonization in northern and southern China, to investigate the serotyping, multilocus sequence typing, and antibiotic cross-resistance, and to characterize the mutations in gyrA and parC genes in quinolone resistance-determining region (QRDR). In order to provide a comprehensive view of the location and structure of resistance genes, whole-genome sequencing on III/ST19 MDR isolates were performed. Among 426 GBS, 138 (32.4%) were FQ resistant, with higher prevalence in northern China than in southern China in both neonates (57.8%, 37/64 vs. 21.7%, 39/180) and pregnant women (50.9%, 29/57 vs. 26.4%, 33/125). Serotypes were distributed as III (48.5%), Ib (39.9%), V (6.5%), and Ia (5.1%). Sequence types were mainly ST19 (53.6%) and ST10 (39.1%), followed by ST12 (1.4%), ST17 (1.4%), ST23 (1.4%), and 0.7% each of ST27, ST188, ST197, and ST597. ST19 isolates were more prevalent in southern China than in northern China in both neonates (64.1%, 25/39 vs. 27.0%, 10/37) and pregnant women (81.8%, 27/33 vs. 41.4%, 12/29), whereas ST10 isolates were more common in northern China than in southern China in both neonates (64.9%, 24/37 vs. 20.5%, 8/39) and pregnant women (58.6%, 17/29 vs. 15.2%, 5/33). Serotype III isolates were mainly ST19 (89.6%, 60/67), while Ib isolates were largely ST10 (94.5%, 52/55). Sequencing data revealed several mutations in QRDR, including Ser81Leu in gyrA (99.2%, 130/131), Ser79Phe or Tyr in parC (76.2%, 48/63), and a previously unreported Ile218Thr and Ile219Phe double mutation pattern (49.2%, 31/63) in parC. ST10 isolates were associated with Ser79Phe (84%, 21/25), while ST19 isolates were limited to Ser79Tyr (95.7%, 22/23). A new integrative and conjugative element (ICE) harboring tetM and gyrA genes was identified in a III/ST19 isolate. This study investigates the molecular characteristics of FQ-resistant GBS in northern and southern China, emphasizing the need for continuous surveillance geographically and further research to characterize the mechanisms of ICE transfer.
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Affiliation(s)
- Kankan Gao
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Chunyan Gao
- Clinical Laboratory, Tangshan Municipal Women and Children's Hospital, Tangshan, China
| | - Lianfen Huang
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Xiaoshan Guan
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Wenjing Ji
- Department of Pharmacy Administration and Clinical Pharmacy, School of Pharmacy, Center for Drug Safety and Policy Research, Xi'an Jiaotong University, Xi'an, China
| | - Chien-Yi Chang
- School of Dental Sciences, Newcastle University, Framlington Place, Newcastle upon Tyne, United Kingdom
| | - David J McIver
- Global Health Group, Institute for Global Health Sciences, University of California, San Francisco, San Francisco, CA, United States
| | - Qiulian Deng
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Huamin Zhong
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Yongqiang Xie
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Lei Deng
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Fei Gao
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Lanlan Zeng
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
| | - Haiying Liu
- Clinical Laboratory, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China
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Ma Y, Hao L, Liang Z, Ma J, Ke H, Kang H, Yang H, Wu J, Feng G, Liu Z. Characterization of novel antigenic vaccine candidates for nile tilapia (Oreochromis niloticus) against Streptococcus agalactiae infection. FISH & SHELLFISH IMMUNOLOGY 2020; 105:405-414. [PMID: 32712231 DOI: 10.1016/j.fsi.2020.07.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/23/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
Streptococcus agalactiae is one of the important pathogens responsible for high mortality and economic losses of the tilapia industry worldwide. Based on ten serovars of S. agalactiae infection, subunit vaccine with conserved antigens is promising strategy corresponding stimulated long-term immunity and provides protection for animals against different serotypes of S. agalactiae. In the present study, eight proteins (AP, AL, LivK, ESAT6, essA, essB, essC and esaA) were selected from the S. agalactiae serotype Ia genome as immunogenic antigens with bioinformation and immune experiment assays. These recombinant proteins were successfully obtained through expression in Escherichia coli and the immunogenicity was assessed in tilapia challenge model. The results showed that the recombinant proteins caused high-level-specific antibodies production and high lysozyme activities, suggesting that the recombinant proteins induced specific humoral immune response and innate immune response of tilapia. The signficant increase were observed in the cytokines levels of TNF-α, IL-1β, IFN-γ, cc1, cc2 and immune-related genes levels of CD8α and MHC factors in the spleen and head kidney tissues, suggesting that the recombinant proteins induced immune response of tilapia through cytokines signal pathway and activated high cytotoxic T-lymphocyte (CTL) activity of tilapia. Furthermore, vaccinated tilapia conferred high levels of protection against challenge with a lethal dose of highly virulent serovar Ⅰa (highest RPS was 91.60% in AL and essC protein groups). Our results indicated that the eight recombinant proteins induced high level of immune responses and offered protection against S. agalactiae infection, could be potential subunit vaccine candidates.
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Affiliation(s)
- Yanping Ma
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China
| | - Le Hao
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China
| | - Zhiling Liang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China
| | - Jiangyao Ma
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China
| | - Hao Ke
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China
| | - Huahua Kang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China; Zhaoqing Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Zhaoqing, China
| | - Hongwei Yang
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Jing Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Guoqing Feng
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China
| | - Zhenxing Liu
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences; Key Laboratory of Livestock Disease Prevention of Guangdong Province; Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture and Rural Affairs, PRC, Guangzhou, China.
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Lannes-Costa PS, Baraúna RA, Ramos JN, Veras JFC, Conceição MVR, Vieira VV, de Mattos-Guaraldi AL, Ramos RTJ, Doran KS, Silva A, Nagao PE. Comparative genomic analysis and identification of pathogenicity islands of hypervirulent ST-17 Streptococcus agalactiae Brazilian strain. INFECTION GENETICS AND EVOLUTION 2020; 80:104195. [DOI: 10.1016/j.meegid.2020.104195] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/09/2020] [Accepted: 01/14/2020] [Indexed: 11/29/2022]
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Zhou Y, Liu Y, Luo Y, Zhong H, Huang T, Liang W, Xiao J, Wu W, Li L, Chen M. Large-scale profiling of the proteome and dual transcriptome in Nile tilapia (Oreochromis niloticus) challenged with low- and high-virulence strains of Streptococcus agalactiae. FISH & SHELLFISH IMMUNOLOGY 2020; 100:386-396. [PMID: 32165249 DOI: 10.1016/j.fsi.2020.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/27/2020] [Accepted: 03/04/2020] [Indexed: 06/10/2023]
Abstract
Streptococcus agalactiae is a common pathogen in aquatic animals, especially tilapia, that hinders aquaculture development and leads to serious economic losses. Previously, a S. agalactiae strain named HN016 was identified from infected tilapia, and the attenuated strain YM001 was subsequently obtained by continuous passaging in Tryptic Soy Broth (TSB) medium. YM001 has been demonstrated as a safe vaccine for S. agalactiae infection in tilapia. To understand the molecular bases of the virulence of these two strains, we performed proteomic and transcriptomic analysis to reveal the protein and gene expression changes in the liver and intestine during the infection process. HN016 significantly decreased the contents of white blood cells (WBCs), neutrophils (NEUs), red blood cells (RBCs) and hematocrit (HCT) and increased the levels of total protein (TP), albumin (ALB) and globulin (GLO), while no such significant differences were observed when comparing the control with YM001. During the infection process, pathogenic peptidoglycan hydrolase, CSPA and membrane proteins were significantly differentially expressed between YM001 and HN016. Furthermore, both proteome and transcriptome data showed that the complement and coagulation cascades pathway and the antigen processing and presentation pathway were stimulated in the liver and intestine, respectively, by YM001 infection compared to HN016 infection. The interaction network analysis of key virulence genes from pathogens suggested that CSPA, as a key node, affects the expression of DOLPP1, MIPEP, PA2G4, OCIAD1, G3BP1 and CLIC5 with a positive correlation. The present evidence suggests that during the infection process, CSPA was the key genes contributing to low virulence in YM001.
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Affiliation(s)
- Yi Zhou
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, 410081, China; Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Yu Liu
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Yongju Luo
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Huan Zhong
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Ting Huang
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Wanwen Liang
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Jun Xiao
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Wende Wu
- Animal Science and Technology College, Guangxi University, Nanning, 530005, China
| | - Liping Li
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China.
| | - Ming Chen
- Guangxi Key Laboratory of Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China.
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do Nascimento CS, Dos Santos NFB, Ferreira RCC, Taddei CR. Streptococcus agalactiae in pregnant women in Brazil: prevalence, serotypes, and antibiotic resistance. Braz J Microbiol 2019; 50:943-952. [PMID: 31432465 PMCID: PMC6863207 DOI: 10.1007/s42770-019-00129-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 07/26/2019] [Indexed: 10/26/2022] Open
Abstract
Brazilian data for maternal GBS colonization shows different prevalence rates. This conflicting data may be related to the absence of an official recommendation from the Federal Brazilian Health Authorities describing guidelines and protocols to perform GBS screening in pregnant women, in both public and private clinics. In the present review, we evaluated published reports addressing the prevalence of GBS in different regions of the country, methods used, and, when available, information regarding antibiotic resistance and serological typing of clinical isolates. According to this review, GBS prevalence in pregnant women in Brazil ranged from 4.2 to 28.4%, in the last 10 years. Serotype Ia was the most prevalent. The highest antibiotic resistance rates were found for tetarcycline, although its use to treat GBS infections is not common. Our results also show high resistance rates to clindamycin and erythromycin, which are commonly used as an alternative to penicillin in GBS infecctions. The increased antibiotic resistance, variations in serotype distribution, and high GBS prevalences need to be further investigated. Based on the present situation, recommendations regarding GBS surveillance in the country were raised and may improve our strategies for preventing neonatal infections.
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Affiliation(s)
- Cilicia S do Nascimento
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, Brazil
| | - Nayara F B Dos Santos
- Department of Microbiology, Biomedical Science Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Rita C C Ferreira
- Department of Microbiology, Biomedical Science Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Carla R Taddei
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo (USP), São Paulo, Brazil.
- School of Arts, Sciences and Humanities, University of São Paulo (USP), São Paulo, Brazil.
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Glutathione Synthesis Contributes to Virulence of Streptococcus agalactiae in a Murine Model of Sepsis. J Bacteriol 2019; 201:JB.00367-19. [PMID: 31331978 DOI: 10.1128/jb.00367-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/10/2019] [Indexed: 01/09/2023] Open
Abstract
Streptococcus agalactiae, a leading cause of sepsis and meningitis in neonates, utilizes multiple virulence factors to survive and thrive within the human host during an infection. Unique among the pathogenic streptococci, S. agalactiae uses a bifunctional enzyme encoded by a single gene (gshAB) to synthesize glutathione (GSH), a major antioxidant in most aerobic organisms. Since S. agalactiae can also import GSH, similar to all other pathogenic streptococcal species, the contribution of GSH synthesis to the pathogenesis of S. agalactiae disease is not known. In the present study, gshAB deletion mutants were generated in strains representing three of the most prevalent clinical serotypes of S. agalactiae and were compared against isogenic wild-type and gshAB knock-in strains. When cultured in vitro in a chemically defined medium under nonstress conditions, each mutant and its corresponding wild type had comparable growth rates, generation times, and growth yields. However, gshAB deletion mutants were found to be more sensitive than wild-type or gshAB knock-in strains to killing and growth inhibition by several different reactive oxygen species. Furthermore, deletion of gshAB in S. agalactiae strain COH1 significantly attenuated virulence compared to the wild-type or gshAB knock-in strains in a mouse model of sepsis. Taken together, these data establish that GSH is a virulence factor important for resistance to oxidative stress and that de novo GSH synthesis plays a crucial role in S. agalactiae pathogenesis and further suggest that the inhibition of GSH synthesis may provide an opportunity for the development of novel therapies targeting S. agalactiae disease.IMPORTANCE Approximately 10 to 30% of women are naturally and asymptomatically colonized by Streptococcus agalactiae However, transmission of S. agalactiae from mother to newborn during vaginal birth is a leading cause of neonatal meningitis. Although colonized mothers who are at risk for transmission to the newborn are treated with antibiotics prior to delivery, S. agalactiae is becoming increasingly resistant to current antibiotic therapies, and new treatments are needed. This research reveals a critical stress resistance pathway, glutathione synthesis, that is utilized by S. agalactiae and contributes to its pathogenesis. Understanding the role of this unique bifunctional glutathione synthesis enzyme in S. agalactiae during sepsis may help elucidate why S. agalactiae produces such an abundance of glutathione compared to other bacteria.
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Al-Saryi N, Ibrahim SA, AL-Kadmy IM, Hetta HF. Whole genome sequencing of Streptococcus pneumoniae serotype 33C causing fatal sepsis in a hospitalized patient with nephrotic syndrome. GENE REPORTS 2019. [DOI: 10.1016/j.genrep.2019.100434] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ayala OD, Doster RS, Manning SD, O’Brien CM, Aronoff DM, Gaddy JA, Mahadevan-Jansen A. Raman microspectroscopy differentiates perinatal pathogens on ex vivo infected human fetal membrane tissues. JOURNAL OF BIOPHOTONICS 2019; 12:e201800449. [PMID: 31162821 PMCID: PMC6902120 DOI: 10.1002/jbio.201800449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/28/2019] [Accepted: 06/02/2019] [Indexed: 06/01/2023]
Abstract
Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is a major cause of chorioamnionitis and neonatal sepsis. This study evaluates Raman spectroscopy (RS) to identify spectral characteristics of infection and differentiate GBS from Escherichia coli and Staphylococcus aureus during ex vivo infection of human fetal membrane tissues. Unique spectral features were identified from colonies grown on agar and infected fetal membrane tissues. Multinomial logistic regression analysis accurately identified GBS infected tissues with 100.0% sensitivity and 88.9% specificity. Together, these findings support further investigation into the use of RS as an emerging microbiologic diagnostic tool and intrapartum screening test for GBS carriage.
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Affiliation(s)
- Oscar D. Ayala
- Biophotonics Center, Vanderbilt University, Nashville, TN 37232, U.S.A
- Department of Biomedical Engineering, Vanderbilt University, Nashville TN 37232, U.S.A
| | - Ryan S. Doster
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
| | - Shannon D. Manning
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, U.S.A
| | - Christine M. O’Brien
- Biophotonics Center, Vanderbilt University, Nashville, TN 37232, U.S.A
- Department of Biomedical Engineering, Vanderbilt University, Nashville TN 37232, U.S.A
| | - David M. Aronoff
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
- Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
| | - Jennifer A. Gaddy
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, U.S.A
- Tennessee Valley Healthcare Systems, Department of Veterans Affairs, Nashville, Tennessee, U.S.A
| | - Anita Mahadevan-Jansen
- Biophotonics Center, Vanderbilt University, Nashville, TN 37232, U.S.A
- Department of Biomedical Engineering, Vanderbilt University, Nashville TN 37232, U.S.A
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42
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Colicin Z, a structurally and functionally novel colicin type that selectively kills enteroinvasive Escherichia coli and Shigella strains. Sci Rep 2019; 9:11127. [PMID: 31366939 PMCID: PMC6668396 DOI: 10.1038/s41598-019-47488-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/16/2019] [Indexed: 01/14/2023] Open
Abstract
Colicin production in Escherichia coli (E. coli) strains represents an important trait with regard to microbial survival and competition in the complex intestinal environment. A novel colicin type, colicin Z (26.3 kDa), was described as a product of an original producer, extraintestinal E. coli B1356 strain, isolated from the anorectal abscess of a 17 years-old man. The 4,007 bp plasmid (pColZ) was completely sequenced and colicin Z activity (cza) and colicin Z immunity (czi) genes were identified. The cza and czi genes are transcribed in opposite directions and encode for 237 and 151 amino acid-long proteins, respectively. Colicin Z shows a narrow inhibitory spectrum, being active only against enteroinvasive E. coli (EIEC) and Shigella strains via CjrC receptor recognition and CjrB- and ExbB-, ExbD-mediated colicin translocation. All tested EIEC and Shigella strains isolated between the years 1958–2010 were sensitive to colicin Z. The lethal effect of colicin Z was found to be directed against cell wall peptidoglycan (PG) resulting in PG degradation, as revealed by experiments with Remazol Brilliant Blue-stained purified peptidoglycans and with MALDI-TOF MS analyses of treated PG. Colicin Z represents a new class of colicins that is structurally and functionally distinct from previously studied colicin types.
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43
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Chen SL. Genomic Insights Into the Distribution and Evolution of Group B Streptococcus. Front Microbiol 2019; 10:1447. [PMID: 31316488 PMCID: PMC6611187 DOI: 10.3389/fmicb.2019.01447] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 06/11/2019] [Indexed: 01/31/2023] Open
Abstract
Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is a bacteria with truly protean biology. It infects a variety of hosts, among which the most commonly studied are humans, cattle, and fish. GBS holds a singular position in the history of bacterial genomics, as it was the substrate used to describe one of the first major conceptual advances of comparative genomics, the idea of the pan-genome. In this review, I describe a brief history of GBS and the major contributions of genomics to understanding its genome plasticity and evolution as well as its molecular epidemiology, focusing on the three hosts mentioned above. I also discuss one of the major recent paradigm shifts in our understanding of GBS evolution and disease burden: foodborne GBS can cause invasive infections in humans.
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Affiliation(s)
- Swaine L Chen
- Division of Infectious Diseases, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Infectious Diseases Group, Genome Institute of Singapore, Singapore, Singapore
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44
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Renard A, Barbera L, Courtier-Martinez L, Dos Santos S, Valentin AS, Mereghetti L, Quentin R, van der Mee-Marquet NL. phiD12-Like Livestock-Associated Prophages Are Associated With Novel Subpopulations of Streptococcus agalactiae Infecting Neonates. Front Cell Infect Microbiol 2019; 9:166. [PMID: 31192160 PMCID: PMC6546898 DOI: 10.3389/fcimb.2019.00166] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 05/03/2019] [Indexed: 01/14/2023] Open
Abstract
Group B Streptococcus (GBS) is a major cause of invasive disease in neonates worldwide. Monitoring data have revealed a continuing trend toward an increase in neonatal GBS infections, despite the introduction of preventive measures. We investigated this trend, by performing the first ever characterization of the prophage content for 106 GBS strains causing neonatal infections between 2002 and 2018. We determined whether the genome of each strain harbored prophages, and identified the insertion site of each of the prophages identified. We found that 71.7% of the strains carried at least one prophage, and that prophages genetically similar to livestock-associated phiD12, carrying genes potentially involved in GBS pathogenesis (e.g., genes encoding putative virulence factors and factors involved in biofilm formation, bacterial persistence, or adaptation to challenging environments) predominated. The phiD12-like prophages were (1) associated with CC17 and 1 strains (p = 0.002), (2) more frequent among strains recovered during the 2011–2018 period than among those from 2002–2010 (p < 0.001), and (3) located at two major insertion sites close to bacterial genes involved in host adaptation and colonization. Our data provide evidence for a recent increase in lysogeny in GBS, characterized by the acquisition, within the genome, of genetic features typical of animal-associated mobile genetic elements by GBS strains causing neonatal infection. We suggest that lysogeny and phiD12-like prophage genetic elements may have conferred an advantage on GBS strains for adaptation to or colonization of the maternal vaginal tract, or for pathogenicity, and that these factors are currently playing a key role in the increasing ability of GBS strains to infect neonates.
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Affiliation(s)
- Adélaïde Renard
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France
| | - Laurie Barbera
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France
| | - Luka Courtier-Martinez
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France
| | - Sandra Dos Santos
- Cellule Régionale d'Epidémiologie Nosocomiale, Centre d'Appui pour la Prévention des Infections Associées aux Soins CPias Centre val de Loire, Service de Bactériologie et Hygiène, Centre Hospitalier Universitaire, Tours, France
| | - Anne-Sophie Valentin
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France
| | - Laurent Mereghetti
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France.,Cellule Régionale d'Epidémiologie Nosocomiale, Centre d'Appui pour la Prévention des Infections Associées aux Soins CPias Centre val de Loire, Service de Bactériologie et Hygiène, Centre Hospitalier Universitaire, Tours, France
| | - Roland Quentin
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France
| | - Nathalie L van der Mee-Marquet
- Bactéries et Risque Materno-Foetal, UMR 1282, Infectiologie Santé Publique, Université de Tours, Tours, France.,Cellule Régionale d'Epidémiologie Nosocomiale, Centre d'Appui pour la Prévention des Infections Associées aux Soins CPias Centre val de Loire, Service de Bactériologie et Hygiène, Centre Hospitalier Universitaire, Tours, France
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45
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Streptococcus agalactiae Strains with Chromosomal Deletions Evade Detection with Molecular Methods. J Clin Microbiol 2019; 57:JCM.02040-18. [PMID: 30760532 DOI: 10.1128/jcm.02040-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 02/03/2019] [Indexed: 01/28/2023] Open
Abstract
Surveillance of circulating microbial populations is critical for monitoring the performance of a molecular diagnostic test. In this study, we characterized 31 isolates of Streptococcus agalactiae (group B Streptococcus [GBS]) from several geographic locations in the United States and Ireland that contain deletions in or adjacent to the region of the chromosome that encodes the hemolysin gene cfb, the region targeted by the Xpert GBS and GBS LB assays. PCR-negative, culture-positive isolates were recognized during verification studies of the Xpert GBS assay in 12 laboratories between 2012 and 2018. Whole-genome sequencing of 15 GBS isolates from 11 laboratories revealed four unique deletions of chromosomal DNA ranging from 181 bp to 49 kb. Prospective surveillance studies demonstrated that the prevalence of GBS isolates containing deletions in the convenience sample was <1% in three geographic locations but 7% in a fourth location. Among the 15 isolates with chromosomal deletions, multiple pulsed-field gel electrophoresis types were identified, one of which appears to be broadly dispersed across the United States.
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46
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Paoletti LC, Kasper DL. Surface Structures of Group B Streptococcus Important in Human Immunity. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0001-2017. [PMID: 30873933 PMCID: PMC11590616 DOI: 10.1128/microbiolspec.gpp3-0001-2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Indexed: 11/20/2022] Open
Abstract
The surface of the Gram-positive opportunistic pathogen Streptococcus agalactiae, or group B Streptococcus (GBS), harbors several carbohydrate and protein antigens with the potential to be effective vaccines. Capsular polysaccharides of all clinically-relevant GBS serotypes coupled to immunogenic proteins of both GBS and non-GBS origin have undergone extensive testing in animals that led to advanced clinical trials in healthy adult women. In addition, GBS proteins either alone or in combination have been tested in animals; a fusion protein construct has recently advanced to human clinical studies. Given our current understanding of the antigenicity and immunogenicity of the wide array of GBS surface antigens, formulations now exist for the generation of viable vaccines against diseases caused by GBS.
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Affiliation(s)
- Lawrence C Paoletti
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
| | - Dennis L Kasper
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115
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47
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Armistead B, Oler E, Adams Waldorf K, Rajagopal L. The Double Life of Group B Streptococcus: Asymptomatic Colonizer and Potent Pathogen. J Mol Biol 2019; 431:2914-2931. [PMID: 30711542 DOI: 10.1016/j.jmb.2019.01.035] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 01/22/2019] [Accepted: 01/23/2019] [Indexed: 12/22/2022]
Abstract
Group B streptococcus (GBS) is a β-hemolytic gram-positive bacterium that colonizes the lower genital tract of approximately 18% of women globally as an asymptomatic member of the gastrointestinal and/or vaginal flora. If established in other host niches, however, GBS is highly pathogenic. During pregnancy, ascending GBS infection from the vagina to the intrauterine space is associated with preterm birth, stillbirth, and fetal injury. In addition, vertical transmission of GBS during or after birth results in life-threatening neonatal infections, including pneumonia, sepsis, and meningitis. Although the mechanisms by which GBS traffics from the lower genital tract to vulnerable host niches are not well understood, recent advances have revealed that many of the same bacterial factors that promote asymptomatic vaginal carriage also facilitate dissemination and virulence. Furthermore, highly pathogenic GBS strains have acquired unique factors that enhance survival in invasive niches. Several host factors also exist that either subdue GBS upon vaginal colonization or alternatively permit invasive infection. This review summarizes the GBS and host factors involved in GBS's state as both an asymptomatic colonizer and an invasive pathogen. Gaining a better understanding of these mechanisms is key to overcoming the challenges associated with vaccine development and identification of novel strategies to mitigate GBS virulence.
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Affiliation(s)
- Blair Armistead
- Department of Global Health, University of Washington, Seattle 98195, WA, USA; Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle 98101, WA, USA
| | - Elizabeth Oler
- Department of Obstetrics and Gynecology, University of Washington School of Medicine, Seattle 98195, WA, USA
| | - Kristina Adams Waldorf
- Department of Global Health, University of Washington, Seattle 98195, WA, USA; Department of Obstetrics and Gynecology, University of Washington School of Medicine, Seattle 98195, WA, USA; Center for Innate Immunity and Immune Disease, University of Washington, Seattle 98109, WA, USA; Sahlgrenska Academy, Gothenburg University, Gothenburg 413 90, Sweden
| | - Lakshmi Rajagopal
- Department of Global Health, University of Washington, Seattle 98195, WA, USA; Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle 98101, WA, USA; Department of Pediatrics, University of Washington School of Medicine, Seattle 98195, WA, USA.
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48
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Xue Z, Kable ME, Marco ML. Impact of DNA Sequencing and Analysis Methods on 16S rRNA Gene Bacterial Community Analysis of Dairy Products. mSphere 2018; 3:e00410-18. [PMID: 30333179 PMCID: PMC6193606 DOI: 10.1128/msphere.00410-18] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 09/13/2018] [Indexed: 12/17/2022] Open
Abstract
DNA sequencing and analysis methods were compared for 16S rRNA V4 PCR amplicon and genomic DNA (gDNA) mock communities encompassing nine bacterial species commonly found in milk and dairy products. The two communities comprised strain-specific DNA that was pooled before (gDNA) or after (PCR amplicon) the PCR step. The communities were sequenced on the Illumina MiSeq and Ion Torrent PGM platforms and then analyzed using the QIIME 1 (UCLUST) and Divisive Amplicon Denoising Algorithm 2 (DADA2) analysis pipelines with taxonomic comparisons to the Greengenes and Ribosomal Database Project (RDP) databases. Examination of the PCR amplicon mock community with these methods resulted in operational taxonomic units (OTUs) and amplicon sequence variants (ASVs) that ranged from 13 to 118 and were dependent on the DNA sequencing method and read assembly steps. The additional 4 to 109 OTUs/ASVs (from 9 OTUs/ASVs) included assignments to spurious taxa and sequence variants of the 9 species included in the mock community. Comparisons between the gDNA and PCR amplicon mock communities showed that combining gDNAs from the different strains prior to PCR resulted in up to 8.9-fold greater numbers of spurious OTUs/ASVs. However, the DNA sequencing method and paired-end read assembly steps conferred the largest effects on predictions of bacterial diversity, with effect sizes of 0.88 (Bray-Curtis) and 0.32 (weighted Unifrac), independent of the mock community type. Overall, DNA sequencing performed with the Ion Torrent PGM and analyzed with DADA2 and the Greengenes database resulted in the most accurate predictions of the mock community phylogeny, taxonomy, and diversity.IMPORTANCE Validated methods are urgently needed to improve DNA sequence-based assessments of complex bacterial communities. In this study, we used 16S rRNA PCR amplicon and gDNA mock community standards, consisting of nine, dairy-associated bacterial species, to evaluate the most commonly applied 16S rRNA marker gene DNA sequencing and analysis platforms used in evaluating dairy and other bacterial habitats. Our results show that bacterial metataxonomic assessments are largely dependent on the DNA sequencing platform and read curation method used. DADA2 improved sequence annotation compared with QIIME 1, and when combined with the Ion Torrent PGM DNA sequencing platform and the Greengenes database for taxonomic assignment, the most accurate representation of the dairy mock community standards was reached. This approach will be useful for validating sample collection and DNA extraction methods and ultimately investigating bacterial population dynamics in milk- and dairy-associated environments.
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Affiliation(s)
- Zhengyao Xue
- Department of Food Science & Technology, University of California, Davis, California, USA
| | - Mary E Kable
- Department of Food Science & Technology, University of California, Davis, California, USA
| | - Maria L Marco
- Department of Food Science & Technology, University of California, Davis, California, USA
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49
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Cai Q, Fauvart M, Wiederkehr RS, Jones B, Cools P, Goos P, Vaneechoutte M, Stakenborg T. Ultra-fast, sensitive and quantitative on-chip detection of group B streptococci in clinical samples. Talanta 2018; 192:220-225. [PMID: 30348381 DOI: 10.1016/j.talanta.2018.09.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 09/04/2018] [Accepted: 09/11/2018] [Indexed: 12/29/2022]
Abstract
PCR enables sensitive and specific detection of infectious disease agents, but application in point-of-care diagnostic testing remains scarce. A compact tool that runs PCR assays in less than a few minutes and that relies on mass-producible, disposable reactors could revolutionize while-you-wait molecular testing. We here exploit well-established semiconductor manufacturing processes to produce silicon ultra-fast quantitative PCR (UF-qPCR) chips that can run PCR protocols with limited assay optimization. A total of 110 clinical samples were analyzed for the detection of group B streptococci using both a validated benchtop and an on-chip qPCR assay. For the on-chip assay, the total reaction time was reduced after optimization to less than 5 min. The standard curve, spanning a concentration range of 5 log units, yielded a PCR efficiency of 94%. The sensitivity obtained was 96% (96/100; CI: 90-98%) and the specificity 70% (7/10; CI: 40-90%). We show that if melting analyses would be integrated, the obtained sensitivity would drop slightly to 93% (CI: 86-96%), while the specificity would increase to 100% (CI: 72% - 100%). In comparison to the benchtop reference qPCR assay performed on a LightCycler©96, the on-chip assay demonstrated a highly significant qualitative (Spearman's rank correlation) and quantitative (linear regression) correlation. Using a mass-producible qPCR chip and limited assay optimization, we were able to develop a validated qPCR protocol that can be carried out in less than five minutes. The analytical performance of the microchip-based UF-qPCR system was shown to match that of a benchtop assay. This is the first report to provide UF-qPCR validation using clinical samples. We demonstrate that qPCR-based while-you-wait testing is feasible without jeopardizing assay performance.
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Affiliation(s)
- Qing Cai
- Imec, Kapeldreef 75, B-3001 Leuven, Belgium
| | | | | | | | - Piet Cools
- Laboratory for Bacteriology Research, Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, Heymanslaan 10 185, Entrance 38 (MRB2), 9000 Gent, Belgium
| | - Peter Goos
- Division of Mechatronics, Biostatistics and Sensors (MeBioS), KU Leuven Kasteelpark Arenberg 30 - bus 2456, 3001 Leuven, Belgium; Department of Engineering Management, University of Antwerp, 2000 Antwerpen, Belgium
| | - Mario Vaneechoutte
- Laboratory for Bacteriology Research, Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, Heymanslaan 10 185, Entrance 38 (MRB2), 9000 Gent, Belgium
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Phenotypic and molecular analysis of nontypeable Group B streptococci: identification of cps2a and hybrid cps2a/cps5 Group B streptococcal capsule gene clusters. Emerg Microbes Infect 2018; 7:137. [PMID: 30087323 PMCID: PMC6081472 DOI: 10.1038/s41426-018-0138-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/11/2018] [Accepted: 06/23/2018] [Indexed: 11/08/2022]
Abstract
The Group B streptococcus (GBS) can express a capsular polysaccharide (CPS). There are ten recognized CPSs (Ia, Ib, and II-IX). A GBS isolate is considered nontypeable (NT) when CPS cannot be identified as one of ten types. Two groups of GBS NT isolates were studied, isolates without surface sialic acid (sia(-)) and isolates with surface sialic acid (sia(+)). The first objective was to characterize NT sia(-) isolates that failed CPS identification by an immunodiffusion antisera typing assay and a RT-PCR capsule typing assay. NT sia(-) isolates were characterized by assaying phenotypic changes and identifying covR/S mutations that may potentially have a role in the altered phenotypes. The second objective was to characterize NT sia(+) isolates that failed to identify as one of the ten CPS types by an immundiffusion antisera-based typing assay and a RT-PCR capsule typing assay yet expressed capsule. Fifteen NT sia(-) isolates displayed increased β hemolysis/orange pigmentation, decreased CAMP activity, inability to form biofilm, and susceptibility to phagocytosis by human blood. DNA sequence analysis of the covR/S genes in the sia(-) isolates found mutations in 14 of 15 isolates assayed. These mutations in the covR/S genes may potentially contribute to lack of expression of phenotypic traits assayed in vitro. For the three NT sia(+) isolates, whole-genome sequence analyses identified two isolates with cps gene clusters identical to the recently described and uncommon CPSIIa type. The third isolate possessed a hybrid cluster containing cps genes for both CPSIIa and CPSV suggesting recombination between these two gene clusters.
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