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Medvedev KE, Zhang J, Schaeffer RD, Kinch LN, Cong Q, Grishin NV. Structure classification of the proteins from Salmonella enterica pangenome revealed novel potential pathogenicity islands. Sci Rep 2024; 14:12260. [PMID: 38806511 PMCID: PMC11133325 DOI: 10.1038/s41598-024-60991-x] [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: 02/20/2024] [Accepted: 04/30/2024] [Indexed: 05/30/2024] Open
Abstract
Salmonella enterica is a pathogenic bacterium known for causing severe typhoid fever in humans, making it important to study due to its potential health risks and significant impact on public health. This study provides evolutionary classification of proteins from Salmonella enterica pangenome. We classified 17,238 domains from 13,147 proteins from 79,758 Salmonella enterica strains and studied in detail domains of 272 proteins from 14 characterized Salmonella pathogenicity islands (SPIs). Among SPIs-related proteins, 90 proteins function in the secretion machinery. 41% domains of SPI proteins have no previous sequence annotation. By comparing clinical and environmental isolates, we identified 3682 proteins that are overrepresented in clinical group that we consider as potentially pathogenic. Among domains of potentially pathogenic proteins only 50% domains were annotated by sequence methods previously. Moreover, 36% (1330 out of 3682) of potentially pathogenic proteins cannot be classified into Evolutionary Classification of Protein Domains database (ECOD). Among classified domains of potentially pathogenic proteins the most populated homology groups include helix-turn-helix (HTH), Immunoglobulin-related, and P-loop domains-related. Functional analysis revealed overrepresentation of these protein in biological processes related to viral entry into host cell, antibiotic biosynthesis, DNA metabolism and conformation change, and underrepresentation in translational processes. Analysis of the potentially pathogenic proteins indicates that they form 119 clusters or novel potential pathogenicity islands (NPPIs) within the Salmonella genome, suggesting their potential contribution to the bacterium's virulence. One of the NPPIs revealed significant overrepresentation of potentially pathogenic proteins. Overall, our analysis revealed that identified potentially pathogenic proteins are poorly studied.
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Affiliation(s)
- Kirill E Medvedev
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
| | - Jing Zhang
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - R Dustin Schaeffer
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Lisa N Kinch
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Qian Cong
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Nick V Grishin
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
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2
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Han J, Aljahdali N, Zhao S, Tang H, Harbottle H, Hoffmann M, Frye JG, Foley SL. Infection biology of Salmonella enterica. EcoSal Plus 2024:eesp00012023. [PMID: 38415623 DOI: 10.1128/ecosalplus.esp-0001-2023] [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: 02/17/2023] [Accepted: 07/31/2023] [Indexed: 02/29/2024]
Abstract
Salmonella enterica is the leading cause of bacterial foodborne illness in the USA, with an estimated 95% of salmonellosis cases due to the consumption of contaminated food products. Salmonella can cause several different disease syndromes, with the most common being gastroenteritis, followed by bacteremia and typhoid fever. Among the over 2,600 currently identified serotypes/serovars, some are mostly host-restricted and host-adapted, while the majority of serotypes can infect a broader range of host species and are associated with causing both livestock and human disease. Salmonella serotypes and strains within serovars can vary considerably in the severity of disease that may result from infection, with some serovars that are more highly associated with invasive disease in humans, while others predominantly cause mild gastroenteritis. These observed clinical differences may be caused by the genetic make-up and diversity of the serovars. Salmonella virulence systems are very complex containing several virulence-associated genes with different functions that contribute to its pathogenicity. The different clinical syndromes are associated with unique groups of virulence genes, and strains often differ in the array of virulence traits they display. On the chromosome, virulence genes are often clustered in regions known as Salmonella pathogenicity islands (SPIs), which are scattered throughout different Salmonella genomes and encode factors essential for adhesion, invasion, survival, and replication within the host. Plasmids can also carry various genes that contribute to Salmonella pathogenicity. For example, strains from several serovars associated with significant human disease, including Choleraesuis, Dublin, Enteritidis, Newport, and Typhimurium, can carry virulence plasmids with genes contributing to attachment, immune system evasion, and other roles. The goal of this comprehensive review is to provide key information on the Salmonella virulence, including the contributions of genes encoded in SPIs and plasmids during Salmonella pathogenesis.
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Affiliation(s)
- Jing Han
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Nesreen Aljahdali
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
- Biological Science Department, College of Science, King Abdul-Aziz University, Jeddah, Saudi Arabia
| | - Shaohua Zhao
- Center for Veterinary Medicine, U.S. Food and Drug Administration, Rockville, Maryland, USA
| | - Hailin Tang
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Heather Harbottle
- Center for Veterinary Medicine, U.S. Food and Drug Administration, Rockville, Maryland, USA
| | - Maria Hoffmann
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland, USA
| | - Jonathan G Frye
- Agricutlutral Research Service, U.S. Department of Agriculture, Athens, Georgia, USA
| | - Steven L Foley
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
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3
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Fei X, Schroll C, Huang K, Christensen JP, Christensen H, Lemire S, Kilstrup M, Thomsen LE, Jelsbak L, Olsen JE. The global transcriptomes of Salmonella enterica serovars Gallinarum, Dublin and Enteritidis in the avian host. Microb Pathog 2023; 182:106236. [PMID: 37419218 DOI: 10.1016/j.micpath.2023.106236] [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: 05/03/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/09/2023]
Abstract
Salmonella enterica serovar Gallinarum causes Fowl Typhoid in poultry, and it is host specific to avian species. The reasons why S. Gallinarum is restricted to avians, and at the same time predominately cause systemic infections in these hosts, are unknown. In the current study, we developed a surgical approach to study gene expression inside the peritoneal cavity of hens to shed light on this. Strains of the host specific S. Gallinarum, the cattle-adapted S. Dublin and the broad host range serovar, S. Enteritidis, were enclosed in semi-permeable tubes and surgically placed for 4 h in the peritoneal cavity of hens and for control in a minimal medium at 41.2 °C. Global gene-expression under these conditions was compared between serovars using tiled-micro arrays with probes representing the genome of S. Typhimurium, S. Dublin and S. Gallinarum. Among other genes, genes of SPI-13, SPI-14 and the macrophage survival gene mig-14 were specifically up-regulated in the host specific serovar, S. Gallinarum, and further studies into the role of these genes in host specific infection are highly indicated. Analysis of pathways and GO-terms, which were enriched in the host specific S. Gallinarum without being enriched in the two other serovars indicated that host specificity was characterized by a metabolic fine-tuning as well as unique expression of virulence associated pathways. The cattle adapted serovar S. Dublin differed from the two other serovars by a lack of up-regulation of genes encoded in the virulence associated pathogenicity island 2, and this may explain the inability of this serovar to cause disease in poultry.
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Affiliation(s)
- Xiao Fei
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; Jiangsu Key Laboratory of Zoonosis, Yangzhou University, China
| | - Casper Schroll
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Kaisong Huang
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; Zhuhai Center for Disease Control and Prevention, Zhuhai, China
| | - Jens P Christensen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Henrik Christensen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Sebastien Lemire
- Department of Systems Biology, Technical University of Denmark, Denmark
| | - Mogens Kilstrup
- Department of Systems Biology, Technical University of Denmark, Denmark
| | - Line E Thomsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Lotte Jelsbak
- Department of Science and Environment, Roskilde University, Denmark
| | - John E Olsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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4
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Chatterjee R, Chowdhury AR, Mukherjee D, Chakravortty D. From Eberthella typhi to Salmonella Typhi: The Fascinating Journey of the Virulence and Pathogenicity of Salmonella Typhi. ACS OMEGA 2023; 8:25674-25697. [PMID: 37521659 PMCID: PMC10373206 DOI: 10.1021/acsomega.3c02386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 06/30/2023] [Indexed: 08/01/2023]
Abstract
Salmonella Typhi (S. Typhi), the invasive typhoidal serovar of Salmonella enterica that causes typhoid fever in humans, is a severe threat to global health. It is one of the major causes of high morbidity and mortality in developing countries. According to recent WHO estimates, approximately 11-21 million typhoid fever illnesses occur annually worldwide, accounting for 0.12-0.16 million deaths. Salmonella infection can spread to healthy individuals by the consumption of contaminated food and water. Typhoid fever in humans sometimes is accompanied by several other critical extraintestinal complications related to the central nervous system, cardiovascular system, pulmonary system, and hepatobiliary system. Salmonella Pathogenicity Island-1 and Salmonella Pathogenicity Island-2 are the two genomic segments containing genes encoding virulent factors that regulate its invasion and systemic pathogenesis. This Review aims to shed light on a comparative analysis of the virulence and pathogenesis of the typhoidal and nontyphoidal serovars of S. enterica.
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Affiliation(s)
- Ritika Chatterjee
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Atish Roy Chowdhury
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Debapriya Mukherjee
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Dipshikha Chakravortty
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
- Centre
for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, Karnataka 560012, India
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5
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Chacón RD, Ramírez M, Rodríguez-Cueva CL, Sánchez C, Quispe-Rojas WU, Astolfi-Ferreira CS, Piantino Ferreira AJ. Genomic Characterization and Genetic Profiles of Salmonella Gallinarum Strains Isolated from Layers with Fowl Typhoid in Colombia. Genes (Basel) 2023; 14:genes14040823. [PMID: 37107581 PMCID: PMC10138188 DOI: 10.3390/genes14040823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/28/2023] [Accepted: 03/28/2023] [Indexed: 04/29/2023] Open
Abstract
Salmonella Gallinarum (SG) is the causative agent of fowl typhoid (FT), a disease that is harmful to the poultry industry. Despite sanitation and prophylactic measures, this pathogen is associated with frequent disease outbreaks in developing countries, causing high morbidity and mortality. We characterized the complete genome sequence of Colombian SG strains and then performed a comparative genome analysis with other SG strains found in different regions worldwide. Eight field strains of SG plus a 9R-derived vaccine were subjected to whole-genome sequencing (WGS) and bioinformatics analysis, and the results were used for subsequent molecular typing; virulome, resistome, and mobilome characterization; and a comparative genome study. We identified 26 chromosome-located resistance genes that mostly encode efflux pumps, and point mutations were found in gyrase genes (gyrA and gyrB), with the gyrB mutation S464T frequently found in the Colombian strains. Moreover, we detected 135 virulence genes, mainly in 15 different Salmonella pathogenicity islands (SPIs). We generated an SPI profile for SG, including C63PI, CS54, ssaD, SPI-1, SPI-2, SPI-3, SPI-4, SPI-5, SPI-6, SPI-9, SPI-10, SPI-11, SPI-12, SPI-13, and SPI-14. Regarding mobile genetic elements, we found the plasmids Col(pHAD28) and IncFII(S) in most of the strains and 13 different prophage sequences, indicating a frequently obtained profile that included the complete phage Gifsy_2 and incomplete phage sequences resembling Escher_500465_2, Shigel_SfIV, Entero_mEp237, and Salmon_SJ46. This study presents, for the first time, the genomic content of Colombian SG strains and a profile of the genetic elements frequently found in SG, which can be further studied to clarify the pathogenicity and evolutionary characteristics of this serotype.
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Affiliation(s)
- Ruy D Chacón
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo 05508-270, Brazil
- Inter-Units Program in Biotechnology, University of São Paulo, São Paulo 05508-900, Brazil
| | - Manuel Ramírez
- Unidad de Bioinformática, Centro de Investigaciones Tecnológicas, Biomédicas y Medioambientales, Bellavista 07006, Peru
| | - Carmen L Rodríguez-Cueva
- Laboratory of Biology and Molecular Genetics, Faculty of Veterinary Medicine, Universidad Nacional Mayor de San Marcos, Lima 15021, Peru
| | - Christian Sánchez
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), 28040 Madrid, Spain
| | - Wilma Ursula Quispe-Rojas
- Laboratory of Molecular Microbiology and Biotechnology, Faculty of Biological Sciences, Universidad Nacional Mayor de San Marcos, Lima 15081, Peru
| | - Claudete S Astolfi-Ferreira
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo 05508-270, Brazil
| | - Antonio J Piantino Ferreira
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo 05508-270, Brazil
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6
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Karmakar K, Chakraborty S, Kumar JR, Nath U, Nataraja KN, Chakravortty D. Role of lactoyl-glutathione lyase of Salmonella in the colonization of plants under salinity stress. Res Microbiol 2023; 174:104045. [PMID: 36842715 DOI: 10.1016/j.resmic.2023.104045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 02/17/2023] [Accepted: 02/18/2023] [Indexed: 02/28/2023]
Abstract
Salmonella, a foodborne human pathogen, can colonize the members of the kingdom Plantae. However, the basis of the persistence of Salmonella in plants is largely unknown. Plants encounter various biotic and abiotic stress agents in soil. We conjectured that methylglyoxal (MG), one of the common metabolites that accumulate in plants during both biotic and abiotic stress, plays a role in regulating the plant-Salmonella interaction. The interaction of Salmonella Typhimurium with plants under salinity stress was investigated. It was observed that wild-type Salmonella Typhimurium can efficiently colonize the root, but mutant bacteria lacking MG detoxifying enzyme, lactoyl-glutathione lyase (Lgl), showed lower colonization in roots exclusively under salinity stress. This colonization defect is due to the poor viability of the mutated bacterial strains under these conditions. This is the first report to prove the role of MG-detoxification genes in the colonization of stressed plants and highlights the possible involvement of metabolic genes in the evolution of the plant-associated life of Salmonella.
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Affiliation(s)
- Kapudeep Karmakar
- Regional Research Station, Terai Zone, Uttar Banga Krishi Viswavidyalaya, Coochbehar-736165, India.
| | - Sangeeta Chakraborty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
| | - Jyothsna R Kumar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
| | - Utpal Nath
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
| | - Karaba N Nataraja
- Department of Crop Physiology, University of Agricultural Science, Bangalore 560012, India.
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India; Adjunct Faculty, School of Biology, Indian Institute of Science and Educational Research, Thiruvananthapuram 695551, India.
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7
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Luo M, She Y, Jiang Y, Xie L, Yang C, Qiu Y, Cai R, Li Y, Xu L, Hu L, Wang L, Wu S, Chen Q, Shi X, Jiang M, Hu Q. Population dynamics and antimicrobial resistance of Salmonella Derby ST40 from Shenzhen, China. Front Microbiol 2022; 13:1065672. [PMID: 36605513 PMCID: PMC9808032 DOI: 10.3389/fmicb.2022.1065672] [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: 10/10/2022] [Accepted: 11/28/2022] [Indexed: 01/07/2023] Open
Abstract
Salmonella enterica subsp. enterica serovar Derby (S. Derby) is one of the most common serotypes responsible for salmonellosis in humans and animals. The two main sequence types (ST) observed in China are ST40 and ST71, with ST40 presently being the most common in Shenzhen. Recent years have seen an increasing number of cases of salmonella caused by ST40 S. Derby, but the epidemiology is not clear. We gathered 314 ST40 S. Derby isolates from food and patient samples for 11 years in Shenzhen; 76 globally prevalent representative strains were also collected. Whole-genome sequencing (WGS) combined with drug resistance phenotyping was used to examine population structural changes, inter-host associations, drug resistance characteristics, and the food-transmission risks of ST40 S. Derby in Shenzhen over this period. The S. enterica evolutionary tree is divided into five clades, and the strains isolated in Shenzhen were primarily concentrated in Clades 2, 4, and 5, and thus more closely related to strains from Asian (Thailand and Vietnam) than European countries. Our 11-year surveillance of S. Derby in Shenzhen showed that Clades 2, 4, and 5 are now the dominant epidemic branches, and branches 2 and 5 are heavily multi-drug resistant. The main resistance pattern is ampicillin-tetracycline-ciprofloxacin-chloramphenicol-nalidixic acid-streptomycin-sulfamethoxazole/trimethoprim. This may lead to a trend of increasing resistance to ST40 S. Derby in Shenzhen. Using a segmentation of ≤3 SNP among clone clusters, we discovered that Clades 2 and 4 contained multiple clonal clusters of both human- and food-derived strains. The food-derived strains were mainly isolated from pig liver, suggesting this food has a high risk of causing disease outbreaks in Shenzhen.
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Affiliation(s)
- Miaomiao Luo
- School of Public Health, Shanxi Medical University, Taiyuan, China
| | - Yiying She
- School of Public Health, Shanxi Medical University, Taiyuan, China
| | - Yixiang Jiang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Li Xie
- School of Public Health, University of South China, Hengyang, China
| | - Chao Yang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Yaqun Qiu
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Rui Cai
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Yinghui Li
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Liangcai Xu
- Shenzhen Futian District Center for Disease Control and Prevention, Shenzhen, China
| | - Lulu Hu
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Lei Wang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Shuang Wu
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Qiongcheng Chen
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Xiaolu Shi
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Min Jiang
- Shenzhen Center for Disease Control and Prevention, Shenzhen, China,Min Jiang,
| | - Qinghua Hu
- School of Public Health, Shanxi Medical University, Taiyuan, China,Shenzhen Center for Disease Control and Prevention, Shenzhen, China,*Correspondence: Qinghua Hu,
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Tahir H, Basit A, Tariq H, Haider Z, Ullah A, Hayat Z, Rehman SU. Coupling CRISPR/Cas9 and Lambda Red Recombineering System for Genome Editing of Salmonella Gallinarum and the Effect of ssaU Knock-Out Mutant on the Virulence of Bacteria. Biomedicines 2022; 10:biomedicines10123028. [PMID: 36551784 PMCID: PMC9776377 DOI: 10.3390/biomedicines10123028] [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] [Received: 10/31/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 11/25/2022] Open
Abstract
The poultry industry in developing countries still faces a significant threat from fowl typhoid, a disease caused by Salmonella Gallinarum that has been well contained in more economically developed countries. In addition to the virulence exhibited by large virulence plasmid (85 kb), Salmonella Pathogenicity Island 2 in S. Gallinarum plays a key role in mediating disease through its type III secretion systems (TTSS). The TTSS secrete effector protein across the Salmonella containing vacuoles and mediate the internalization of bacteria by modulating vesicular passage. In this study, candidate virulent ssaU gene (~1 kb) encoding type III secretion system was successfully deleted from indigenously isolated S. Gallinarum genome through homology-directed repair using CRISPR/Cas9 and lambda recombination systems. CRISPR/Cas9-based genome editing of poultry-derived Salmonella Gallinarum has not been previously reported, which might be linked to a lack of efficiency in its genetic tools. This is the first study which demonstrates a complete CRISPR/Cas9-based gene deletion from this bacterial genome. More importantly, a poultry experimental model was employed to assess the virulence potential of this mutant strain (ΔssaU_SG18) which was unable to produce any mortality in the experimentally challenged birds as compared to the wild type strain. No effect on weight gain was observed whereas bacteria were unable to colonize the intestine and liver in our challenge model. This in vivo loss of virulence in mutant strain provides an excellent functionality of this system to be useful in live vaccine development against this resistant and patho genic bacteria.
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Affiliation(s)
- Hamza Tahir
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan
| | - Abdul Basit
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan
- School of Biology, University of St Andrews, St Andrews KY16 9AJ, UK
| | - Hafsa Tariq
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan
| | - Zulquernain Haider
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan
| | - Asim Ullah
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan
- Division of Infection and Immunity, The Roslin Institute, University of Edinbrugh, Edinburgh EH8 9YL, UK
| | - Zafar Hayat
- Department of Animal Nutrition, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
- Department of Animal Sciences, University of Sargodha, Sargodha 40100, Pakistan
| | - Shafiq Ur Rehman
- Division of Infection and Immunity, The Roslin Institute, University of Edinbrugh, Edinburgh EH8 9YL, UK
- Correspondence: ; Tel.: +92-3214905423
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9
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Shikov AE, Belousova ME, Belousov MV, Nizhnikov AA, Antonets KS. Salmonella-Based Biorodenticides: Past Applications and Current Contradictions. Int J Mol Sci 2022; 23:ijms232314595. [PMID: 36498920 PMCID: PMC9736839 DOI: 10.3390/ijms232314595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/03/2022] [Accepted: 11/14/2022] [Indexed: 11/24/2022] Open
Abstract
The idea of using pathogens to control pests has existed since the end of the 19th century. Enterobacteria from the genus Salmonella, discovered at that time, are the causative agents of many serious diseases in mammals often leading to death. Mostly, the strains of Salmonella are able to infect a wide spectrum of hosts belonging to vertebrates, but some of them show host restriction. Several strains of these bacteria have been used as biorodenticides due to the host restriction until they were banned in many countries in the second part of the 20th century. The main reason for the ban was their potential pathogenicity for some domestic animals and poultry and the outbreaks of gastroenteritis in humans. Since that time, a lot of data regarding the host specificity and host restriction of different strains of Salmonella have been accumulated, and the complexity of the molecular mechanisms affecting it has been uncovered. In this review, we summarize the data regarding the history of studying and application of Salmonella-based rodenticides, discuss molecular systems controlling the specificity of Salmonella interactions within its multicellular hosts at different stages of infection, and attempt to reconstruct the network of genes and their allelic variants which might affect the host-restriction mechanisms.
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Affiliation(s)
- Anton E. Shikov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), Pushkin, St. Petersburg 196608, Russia
- Faculty of Biology, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Maria E. Belousova
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), Pushkin, St. Petersburg 196608, Russia
| | - Mikhail V. Belousov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), Pushkin, St. Petersburg 196608, Russia
- Faculty of Biology, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Anton A. Nizhnikov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), Pushkin, St. Petersburg 196608, Russia
- Faculty of Biology, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Kirill S. Antonets
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), Pushkin, St. Petersburg 196608, Russia
- Faculty of Biology, St. Petersburg State University, St. Petersburg 199034, Russia
- Correspondence:
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10
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Basit A, Tahir H, Haider Z, Tariq H, Ullah A, Rehman SU. CRISPR/Cas9-Based Deletion of SpvB Gene From Salmonella gallinarum Leads to Loss of Virulence in Chicken. Front Bioeng Biotechnol 2022; 10:885227. [PMID: 35769104 PMCID: PMC9234527 DOI: 10.3389/fbioe.2022.885227] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 04/25/2022] [Indexed: 12/03/2022] Open
Abstract
Salmonella Gallinarum causes fowl typhoid in poultry leading to a huge economic loss to the poultry industry. The large virulence plasmid of S. gallinarum has been associated with various systemic infections in poultry. A five-gene spanning region (spvRABCD) of 7.8 kb on the large plasmid mainly confers virulence to the bacteria. However, the exact role of these genes in virulence has not been elucidated yet. SpvB exhibits delayed cell death by preventing actin polymerization followed by apoptosis during intracellular infection. The specific role of SpvB in causing the disease is not known yet. In the current study, the SpvB gene was deleted through CRISPR/Cas9 method from a large virulent plasmid of locally isolated S. gallinarum strain (SG18). The homology-directed repair method was used for complete deletion of SpvB gene using the modified pCas9 plasmid. The SpvB-deleted S. gallinarum strain (ΔSpvB_SG18), when tested for its virulence in broiler chicken showed no diseases signs and mortality. In addition, the avirulent strain does not affect the bird’s weight and was rapidly cleared from the liver after infection. However, it cleared from the intestine only after 4–5 days, which suggests that the ΔSpvB_SG18 strain is unable to invade from the intestine to the liver. This is the first study to report a complete gene deletion from the S. gallinarum virulent plasmid and its effect. This method will be useful for the deletion of virulent genes from S. gallinarum, to study their role in pathogenesis, and to prepare an effective vaccine strain for controlling fowl typhoid in poultry.
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Affiliation(s)
- Abdul Basit
- *Correspondence: Abdul Basit, ; Shafiq Ur Rehman ,
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11
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Hudson LK, Constantine-Renna L, Thomas L, Moore C, Qian X, Garman K, Dunn JR, Denes TG. Genomic characterization and phylogenetic analysis of Salmonella enterica serovar Javiana. PeerJ 2020; 8:e10256. [PMID: 33240617 PMCID: PMC7682435 DOI: 10.7717/peerj.10256] [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: 06/09/2020] [Accepted: 10/06/2020] [Indexed: 02/01/2023] Open
Abstract
Salmonella enterica serovar Javiana is the fourth most reported serovar of laboratory-confirmed human Salmonella infections in the U.S. and in Tennessee (TN). Although Salmonella ser. Javiana is a common cause of human infection, the majority of cases are sporadic in nature rather than outbreak-associated. To better understand Salmonella ser. Javiana microbial population structure in TN, we completed a phylogenetic analysis of 111 Salmonella ser. Javiana clinical isolates from TN collected from Jan. 2017 to Oct. 2018. We identified mobile genetic elements and genes known to confer antibiotic resistance present in the isolates, and performed a pan-genome-wide association study (pan-GWAS) to compare gene content between clades identified in this study. The population structure of TN Salmonella ser. Javiana clinical isolates consisted of three genetic clades: TN clade I (n = 54), TN clade II (n = 4), and TN clade III (n = 48). Using a 5, 10, and 25 hqSNP distance threshold for cluster identification, nine, 12, and 10 potential epidemiologically-relevant clusters were identified, respectively. The majority of genes that were found to be over-represented in specific clades were located in mobile genetic element (MGE) regions, including genes encoding integrases and phage structures (91.5%). Additionally, a large portion of the over-represented genes from TN clade II (44.9%) were located on an 87.5 kb plasmid containing genes encoding a toxin/antitoxin system (ccdAB). Additionally, we completed phylogenetic analyses of global Salmonella ser. Javiana datasets to gain a broader insight into the population structure of this serovar. We found that the global phylogeny consisted of three major clades (one of which all of the TN isolates belonged to) and two cgMLST eBurstGroups (ceBGs) and that the branch length between the two Salmonella ser. Javiana ceBGs (1,423 allelic differences) was comparable to those from other serovars that have been reported as polyphyletic (929–2,850 allelic differences). This study demonstrates the population structure of TN and global Salmonella ser. Javiana isolates, a clinically important Salmonella serovar and can provide guidance for phylogenetic cluster analyses for public health surveillance and response.
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Affiliation(s)
- Lauren K Hudson
- Department of Food Science, University of Tennessee, Knoxville, TN, United States of America
| | | | - Linda Thomas
- Division of Laboratory Services, Tennessee Department of Health, Nashville, TN, United States of America
| | - Christina Moore
- Division of Laboratory Services, Tennessee Department of Health, Nashville, TN, United States of America
| | - Xiaorong Qian
- Division of Laboratory Services, Tennessee Department of Health, Nashville, TN, United States of America
| | - Katie Garman
- Tennessee Department of Health, Nashville, TN, United States of America
| | - John R Dunn
- Tennessee Department of Health, Nashville, TN, United States of America
| | - Thomas G Denes
- Department of Food Science, University of Tennessee, Knoxville, TN, United States of America
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12
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Mansour MN, Yaghi J, El Khoury A, Felten A, Mistou MY, Atoui A, Radomski N. Prediction of Salmonella serovars isolated from clinical and food matrices in Lebanon and genomic-based investigation focusing on Enteritidis serovar. Int J Food Microbiol 2020; 333:108831. [PMID: 32854018 DOI: 10.1016/j.ijfoodmicro.2020.108831] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/09/2020] [Accepted: 08/10/2020] [Indexed: 12/17/2022]
Abstract
Salmonella enterica subsp. enterica serovars are considered major causes of food poisoning and we performed this study because Salmonella is a burden in Lebanon. The present study investigated the ability of genomic information to predict serovar using a collection of Salmonella isolates from infected humans (n = 24) and contaminated food (n = 63) in Lebanon. Further, the phylogenomic relationships of the serovar the predominated in Lebanon (i.e., S. Enteritidis; n = 25) were investigated in comparison with isolates from other countries (n = 130) based on coregenome single nucleotide polymorphisms (SNPs). Genetic elements, specifically Salmonella pathogenicity islands (SPIs), plasmid replicons, and antibiotic-resistance genes were screened in S. Enteritidis genomes (n = 155). Our results revealed that the Salmonella serovars identification by seroagglutination from the samples isolated in Lebanon (n = 87) was highly correlated with the genomic-based prediction of serovars (80.4-85.0% with SeqSero1 and 93.1-94.2% with SeqSero2). The Salmonella serovars isolated from human and food samples in Lebanon were mainly Enteritidis (28.7%) and Infantis (26%). To a rare extent, other serovars included Amager, Anatum, Bredeney, Chincol, Heidelberg, Hofit, Kentucky, Montevideo, Muenster, Newport, Schwarzengrund, Senftenberg and Typhimurium. In comparison with other countries, S. Enteritidis samples isolated in Lebanon (56 ± 27 intra-group pairwise SNP differences) presented a strong phylogenomic relativeness at the coregenome level with samples, as for example with samples isolated from Syria (65 ± 31 inter-group pairwise SNP differences). Most of the studied S. Enteritidis genomes encoded 10 SPIs involved in survival in immune cells (i.e. SPIs 1, 2, 3, 4, 5, 12, 13, 14, 16 and 17). The plasmid replicons IncFIB (S)_1 and IncFII (S)_1 encoding elements involved in virulence were identified in the majority of the S. Enteritidis genomes (94% and 96%, respectively), the majority exhibiting aminoglycosides (gene aac(6')-Iaa_1). The IncI_1_Alpha replicon responsible for ampicillin-resistance was only detected in 2 of 25 S. Enteritidis Lebanese strains. Genomic-based risk assessment of Salmonella serovars in Lebanon showed that food imported from Syria might be an origin of the S. Enteritidis human cases in Lebanon. The detection of several SPIs involved in the survival, plasmid replicons involved in virulence, and aminoglycoside-resistance genes, emphasizes that S. Enteritidis is of paramount importance for public health in Lebanon and other countries.
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Affiliation(s)
- Marie Noel Mansour
- Centre d'Analyses et de Recherche (CAR), Unité de Recherche « Technologies et Valorisation Agro-alimentaire » (UR-TVA), Faculty of Sciences, Saint-Joseph University of Beirut, Campus of Sciences and Technologies, Mar Roukos, Lebanon.
| | - Joseph Yaghi
- Centre d'Analyses et de Recherche (CAR), Unité de Recherche « Technologies et Valorisation Agro-alimentaire » (UR-TVA), Faculty of Sciences, Saint-Joseph University of Beirut, Campus of Sciences and Technologies, Mar Roukos, Lebanon.
| | - André El Khoury
- Centre d'Analyses et de Recherche (CAR), Unité de Recherche « Technologies et Valorisation Agro-alimentaire » (UR-TVA), Faculty of Sciences, Saint-Joseph University of Beirut, Campus of Sciences and Technologies, Mar Roukos, Lebanon.
| | - Arnaud Felten
- Paris-Est University, French Agency for Food, Environmental and Occupational Health and Safety (Anses), Laboratory for Food Safety (LSAL), Maisons-Alfort, France.
| | - Michel-Yves Mistou
- Applied Mathematics and Computer Science, From Genomes to the Environment (MaIAGE), National Institute for Agricultural, Food and Environmental Research (INRAE), Université Paris-Saclay, Jouy-en-Josas, France.
| | - Ali Atoui
- Laboratory of Microbiology, Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadat Campus, Beirut, Lebanon.
| | - Nicolas Radomski
- Paris-Est University, French Agency for Food, Environmental and Occupational Health and Safety (Anses), Laboratory for Food Safety (LSAL), Maisons-Alfort, France.
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13
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Joerger RD. Salmonella enterica's "Choice": Itaconic Acid Degradation or Bacteriocin Immunity Genes. Genes (Basel) 2020; 11:genes11070797. [PMID: 32679707 PMCID: PMC7397319 DOI: 10.3390/genes11070797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/08/2020] [Accepted: 07/13/2020] [Indexed: 11/30/2022] Open
Abstract
Itaconic acid is an immunoregulatory metabolite produced by macrophages in response to pathogen invasion. It also exhibits antibacterial activity because it is an uncompetitive inhibitor of isocitrate lyase, whose activity is required for the glyoxylate shunt to be operational. Some bacteria, such as Yersinia pestis, encode enzymes that can degrade itaconic acid and therefore eliminate this metabolic inhibitor. Studies, primarily with Salmonella enterica subspecies enterica serovar Typhimurium, have demonstrated the presence of similar genes in this pathogen and the importance of these genes for the persistence of the pathogen in murine hosts. This minireview demonstrates that, based on Blast searches of 1063 complete Salmonella genome sequences, not all Salmonella serovars possess these genes. It is also shown that the growth of Salmonella isolates that do not possess these genes is sensitive to the acid under glucose-limiting conditions. Interestingly, most of the serovars without the three genes, including serovar Typhi, harbor DNA at the corresponding genomic location that encodes two open reading frames that are similar to bacteriocin immunity genes. It is hypothesized that these genes could be important for Salmonella that finds itself in strong competition with other Enterobacteriacea in the intestinal tract—for example, during inflammation.
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Affiliation(s)
- Rolf D Joerger
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716, USA
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14
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Guo Y, Xu Y, Xiong D, Zhou Y, Kang X, Meng C, Gu D, Jiao X, Pan Z. Molecular characterisation, expression and functional feature of TRAF6 in the King pigeon ( Columba livia). Innate Immun 2020; 26:490-504. [PMID: 32393097 PMCID: PMC7491236 DOI: 10.1177/1753425920920930] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
TNF receptor-associated factor 6 (TRAF6) is a signal transducer, which plays a pivotal role in triggering a variety of signalling cascades. Here, we cloned and identified the TRAF6 gene from the King pigeon. The open reading frame sequence of pigeon TRAF6 (piTRAF6) is 1638 bp long and encodes a 545 aa protein, including a low-complexity domain, RING finger, Zinc finger, coiled coil domain, and meprin and TRAF homology domain. The aa sequence of piTRAF6 shared a strong identity with that of other birds. PiTRAF6 transcripts were broadly expressed in all the tested tissues; piTRAF6 levels were the highest and lowest in the heart and stomach, respectively. Overexpression of piTRAF6 activated NF-κB in a dose-dependent manner and induced IFN-β expression. Upon piTRAF6 knockdown by small interfering RNAs, NF-κB activation was markedly inhibited in HEK293T cells. The expression of piTRAF6, as well as pro-inflammatory cytokines and antiviral molecules, were obviously increased after TLR ligand stimulation and Newcastle disease virus or Salmonella Pullorum inoculation. These results suggest that piTRAF6 may play a key immunoregulatory role in the innate immune response against viral and bacterial infections.
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Affiliation(s)
- Yaxin Guo
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Ying Xu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Dan Xiong
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Yingying Zhou
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Xilong Kang
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Chuang Meng
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Dan Gu
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Xinan Jiao
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
| | - Zhiming Pan
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, PR China.,Jiangsu Key Laboratory of Zoonosis, Yangzhou University, PR China.,Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, PR China.,Joint International Research Laboratory of Agriculture and Agri-product Safety of the Ministry of Education, Yangzhou University, PR China
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15
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Mastrorilli E, Petrin S, Orsini M, Longo A, Cozza D, Luzzi I, Ricci A, Barco L, Losasso C. Comparative genomic analysis reveals high intra-serovar plasticity within Salmonella Napoli isolated in 2005-2017. BMC Genomics 2020; 21:202. [PMID: 32131727 PMCID: PMC7057659 DOI: 10.1186/s12864-020-6588-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 02/18/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Salmonella enterica subsp. enterica serovar Napoli (S. Napoli) is among the top serovars causing human infections in Italy, although it is relatively uncommon in other European countries; it is mainly isolated from humans and the environment, but neither the reservoir nor its route of infection are clearly defined. This serovar is characterized by high genomic diversity, and molecular evidences revealed important similarities with typhoidal serovars. RESULTS 179 S. Napoli genomes as well as 239 genomes of typhoidal and non-typhoidal serovars were analyzed in a comparative genomic study. Phylogenetic analysis and draft genome characterization in terms of Multi Locus Sequence Typing (MLST), plasmid replicons, Salmonella Pathogenicity Islands (SPIs), antimicrobial resistance genes (ARGs), phages, biocide and metal-tolerance genes confirm the high genetic variability of S. Napoli, also revealing a within-serovar phylogenetic structure more complex than previously known. Our work also confirms genomic similarity of S. Napoli to typhoidal serovars (S. Typhi and S. Paratyphi A), with S. Napoli samples clustering primarily according to ST, each being characterized by specific genomic traits. Moreover, two major subclades of S. Napoli can be clearly identified, with ST-474 being biphyletic. All STs span among isolation sources and years of isolation, highlighting the challenge this serovar poses to define its epidemiology and evolution. Altogether, S. Napoli strains carry less SPIs and less ARGs than other non-typhoidal serovars and seldom acquire plasmids. However, we here report the second case of an extended-spectrum β-lactamases (ESBLs) producing S. Napoli strain and the first cases of multidrug resistant (MDR) S. Napoli strains, all isolated from humans. CONCLUSIONS Our results provide evidence of genomic plasticity of S. Napoli, highlighting genomic similarity with typhoidal serovars and genomic features typical of non-typhoidal serovars, supporting the possibility of survival in different niches, both enteric and non-enteric. Presence of horizontally acquired ARGs and MDR profiles rises concerns regarding possible selective pressure exerted by human environment on this pathogen.
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Affiliation(s)
- Eleonora Mastrorilli
- Istituto Zooprofilattico Sperimentale delle Venezie, Microbial Ecology Unit, Legnaro, Italy
- Present address: European Molecular Biology Laboratory, Structural and Computational Biology Unit, Heidelberg, Germany
| | - Sara Petrin
- Istituto Zooprofilattico Sperimentale delle Venezie, Microbial Ecology Unit, Legnaro, Italy
| | - Massimiliano Orsini
- Istituto Zooprofilattico Sperimentale delle Venezie, Microbial Ecology Unit, Legnaro, Italy.
| | - Alessandra Longo
- Istituto Zooprofilattico Sperimentale delle Venezie, Microbial Ecology Unit, Legnaro, Italy
| | - Debora Cozza
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Portici, Italy
| | - Ida Luzzi
- Istituto Superiore di Sanità, Rome, Italy
| | - Antonia Ricci
- Istituto Zooprofilattico Sperimentale delle Venezie, Food Safety Department, Legnaro, Italy
| | - Lisa Barco
- Istituto Zooprofilattico Sperimentale delle Venezie, Food Safety Department, Legnaro, Italy
| | - Carmen Losasso
- Istituto Zooprofilattico Sperimentale delle Venezie, Microbial Ecology Unit, Legnaro, Italy
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16
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Key FM, Posth C, Esquivel-Gomez LR, Hübler R, Spyrou MA, Neumann GU, Furtwängler A, Sabin S, Burri M, Wissgott A, Lankapalli AK, Vågene ÅJ, Meyer M, Nagel S, Tukhbatova R, Khokhlov A, Chizhevsky A, Hansen S, Belinsky AB, Kalmykov A, Kantorovich AR, Maslov VE, Stockhammer PW, Vai S, Zavattaro M, Riga A, Caramelli D, Skeates R, Beckett J, Gradoli MG, Steuri N, Hafner A, Ramstein M, Siebke I, Lösch S, Erdal YS, Alikhan NF, Zhou Z, Achtman M, Bos K, Reinhold S, Haak W, Kühnert D, Herbig A, Krause J. Emergence of human-adapted Salmonella enterica is linked to the Neolithization process. Nat Ecol Evol 2020; 4:324-333. [PMID: 32094538 PMCID: PMC7186082 DOI: 10.1038/s41559-020-1106-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 01/08/2020] [Indexed: 11/13/2022]
Abstract
It has been hypothesized that the Neolithic transition towards an
agricultural and pastoralist economy facilitated the emergence of human adapted
pathogens. Here, we recovered eight Salmonella enterica subsp.
enterica genomes from human skeletons of transitional
foragers, pastoralists, and agro-pastoralists in western Eurasia that were up to
6,500 years old. Despite the high genetic diversity of S.
enterica all ancient bacterial genomes clustered in a single
previously uncharacterized branch that contains S. enterica
adapted to multiple mammalian species. All ancient bacterial genomes from
prehistoric (agro-)pastoralists fall within a part of this branch that also
includes the human-specific S. enterica Paratyphi C,
illustrating the evolution of a human pathogen over a period of five thousand
years. Bacterial genomic comparisons suggest that the earlier ancient strains
were not host specific, differed in pathogenic potential, and experienced
convergent pseudogenization that accompanied their downstream host adaptation.
These observations support the concept that the emergence of human adapted
S. enterica is linked to human cultural
transformations.
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Affiliation(s)
- Felix M Key
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany. .,Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA. .,Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Cosimo Posth
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Luis R Esquivel-Gomez
- Transmission, Infection, Diversification & Evolution Group, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Ron Hübler
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Maria A Spyrou
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Gunnar U Neumann
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Anja Furtwängler
- Institute for Archaeological Sciences, Archaeo- and Palaeogenetics, University of Tuebingen, Tuebingen, Germany
| | - Susanna Sabin
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Marta Burri
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Antje Wissgott
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Aditya Kumar Lankapalli
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Åshild J Vågene
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Matthias Meyer
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Sarah Nagel
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Rezeda Tukhbatova
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.,Laboratory of Structural Biology, Kazan Federal University, Kazan, Russian Federation
| | - Aleksandr Khokhlov
- Samara State University of Social Sciences and Education, Samara, Russian Federation
| | - Andrey Chizhevsky
- Institute of Archaeology named after A.Kh. Khalikov of the Academy of Sciences of the Republic of Tatarstan, Kazan, Russian Federation
| | - Svend Hansen
- Eurasia Department, German Archaeological Institute, Berlin, Germany
| | | | - Alexey Kalmykov
- 'Nasledie' Cultural Heritage Unit, Stavropol, Russian Federation
| | - Anatoly R Kantorovich
- Department of Archaeology, Faculty of History, Lomonosov Moscow State University, Moscow, Russian Federation
| | | | - Philipp W Stockhammer
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.,Institute for Pre- and Protohistoric Archaeology and Archaeology of the Roman Provinces, Ludwig Maximilian University Munich, Munich, Germany
| | - Stefania Vai
- Department of Biology, University of Florence, Florence, Italy
| | - Monica Zavattaro
- Museum of Anthropology and Ethnology, Museum System of the University of Florence, Florence, Italy
| | - Alessandro Riga
- Department of Biology, University of Florence, Florence, Italy
| | - David Caramelli
- Department of Biology, University of Florence, Florence, Italy
| | - Robin Skeates
- Department of Archaeology, Durham University, Durham, UK
| | | | | | - Noah Steuri
- Institute of Archaeological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Albert Hafner
- Institute of Archaeological Sciences and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | | | - Inga Siebke
- Department of Physical Anthropology Institute of Forensic Medicine, University of Bern, Bern, Switzerland
| | - Sandra Lösch
- Department of Physical Anthropology Institute of Forensic Medicine, University of Bern, Bern, Switzerland
| | | | | | - Zhemin Zhou
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Mark Achtman
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Kirsten Bos
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Sabine Reinhold
- Eurasia Department, German Archaeological Institute, Berlin, Germany
| | - Wolfgang Haak
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Denise Kühnert
- Transmission, Infection, Diversification & Evolution Group, Max Planck Institute for the Science of Human History, Jena, Germany
| | - Alexander Herbig
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.
| | - Johannes Krause
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.
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17
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Song X, Zhang H, Liu X, Yuan J, Wang P, Lv R, Yang B, Huang D, Jiang L. The putative transcriptional regulator STM14_3563 facilitates Salmonella Typhimurium pathogenicity by activating virulence-related genes. Int Microbiol 2019; 23:381-390. [PMID: 31832871 DOI: 10.1007/s10123-019-00110-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/24/2019] [Accepted: 11/28/2019] [Indexed: 11/30/2022]
Abstract
Salmonella enterica serovar Typhimurium (S. Typhimurium) is an important gram-negative intracellular pathogen that infects humans and animals. More than 50 putative regulatory proteins have been identified in the S. Typhimurium genome, but few have been clearly defined. In this study, the physiological function and regulatory role of STM14_3563, which encodes a ParD family putative transcriptional regulator in S. Typhimurium, were investigated. Macrophage replication assays and mice experiments revealed that S. Typhimurium showed reduced growth in murine macrophages and attenuated virulence in mice owing to deletion of STM14_3563 gene. RNA sequencing (RNA-Seq) data showed that STM14_3563 exerts wide-ranging effects on gene expression in S. Typhimurium. STM14_3563 activates the expression of several genes encoded in Salmonella pathogenicity island (SPI)-6, SPI-12, and SPI-13, which are required for intracellular replication of S. Typhimurium. Additionally, the global transcriptional regulator Fis was found to directly activate STM14_3563 expression by binding to the STM14_3563 promoter. These results indicate that STM14_3563 is involved in the regulation of a variety of virulence-related genes in S. Typhimurium that contribute to its growth in macrophages and virulence in mice.
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Affiliation(s)
- Xiaorui Song
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China.,College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Huan Zhang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China.,College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Xiaoqian Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China
| | - Jian Yuan
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China
| | - Peisheng Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China.,College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Runxia Lv
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China
| | - Di Huang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China.,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China
| | - Lingyan Jiang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, 300457, China. .,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin, 300071, China. .,Tianjin Key Laboratory of Microbial Functional Genomics, Tianjin, 300457, China.
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18
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Cheng RA, Eade CR, Wiedmann M. Embracing Diversity: Differences in Virulence Mechanisms, Disease Severity, and Host Adaptations Contribute to the Success of Nontyphoidal Salmonella as a Foodborne Pathogen. Front Microbiol 2019; 10:1368. [PMID: 31316476 PMCID: PMC6611429 DOI: 10.3389/fmicb.2019.01368] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 05/31/2019] [Indexed: 12/19/2022] Open
Abstract
Not all Salmonella enterica serovars cause the same disease. S. enterica represents an incredibly diverse species comprising >2,600 unique serovars. While some S. enterica serovars are host-restricted, others infect a wide range of hosts. The diseases that nontyphoidal Salmonella (NTS) serovars cause vary considerably, with some serovars being significantly more likely to cause invasive disease in humans than others. Furthermore, while genomic analyses have advanced our understanding of the genetic diversity of these serovars, they have not been able to fully account for the observed clinical differences. One overarching challenge is that much of what is known about Salmonella's general biology and virulence strategies is concluded from studies examining a select few serovars, especially serovar Typhimurium. As targeted control strategies have been implemented to control select serovars, an increasing number of foodborne outbreaks involving serovars that are less frequently associated with human clinical illness are being detected. Harnessing what is known about the diversity of NTS serovars represents an important factor in achieving the ultimate goal of reducing salmonellosis-associated morbidity and mortality worldwide. In this review we summarize the current understanding of the differences and similarities among NTS serovars, highlighting the virulence mechanisms, genetic differences, and sources that characterize S. enterica diversity and contribute to its success as a foodborne pathogen.
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Affiliation(s)
- Rachel A. Cheng
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Colleen R. Eade
- Department of Population Medicine and Diagnostic Sciences, Cornell University, Ithaca, NY, United States
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, United States
| | - Martin Wiedmann
- Department of Food Science, Cornell University, Ithaca, NY, United States
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19
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Response of the Biocontrol Agent Pseudomonas pseudoalcaligenes AVO110 to Rosellinia necatrix Exudate. Appl Environ Microbiol 2019; 85:AEM.01741-18. [PMID: 30478234 PMCID: PMC6344628 DOI: 10.1128/aem.01741-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 11/17/2018] [Indexed: 01/08/2023] Open
Abstract
Diseases associated with fungal root invasion cause a significant loss of fruit tree production worldwide. The bacterium Pseudomonas pseudoalcaligenes AVO110 controls avocado white root rot disease caused by Rosellinia necatrix by using mechanisms involving competition for nutrients and niches. Here, a functional genomics approach was conducted to identify the bacterial traits involved in the interaction with this fungal pathogen. Our results contribute to a better understanding of the multitrophic interactions established among bacterial biocontrol agents, the plant rhizosphere, and the mycelia of soilborne pathogens. The rhizobacterium Pseudomonas pseudoalcaligenes AVO110, isolated by the enrichment of competitive avocado root tip colonizers, controls avocado white root rot disease caused by Rosellinia necatrix. Here, we applied signature-tagged mutagenesis (STM) during the growth and survival of AVO110 in fungal exudate-containing medium with the goal of identifying the molecular mechanisms linked to the interaction of this bacterium with R. necatrix. A total of 26 STM mutants outcompeted by the parental strain in fungal exudate, but not in rich medium, were selected and named growth-attenuated mutants (GAMs). Twenty-one genes were identified as being required for this bacterial-fungal interaction, including membrane transporters, transcriptional regulators, and genes related to the metabolism of hydrocarbons, amino acids, fatty acids, and aromatic compounds. The bacterial traits identified here that are involved in the colonization of fungal hyphae include proteins involved in membrane maintenance (a dynamin-like protein and ColS) or cyclic-di-GMP signaling and chemotaxis. In addition, genes encoding a DNA helicase (recB) and a regulator of alginate production (algQ) were identified as being required for efficient colonization of the avocado rhizosphere. IMPORTANCE Diseases associated with fungal root invasion cause a significant loss of fruit tree production worldwide. The bacterium Pseudomonas pseudoalcaligenes AVO110 controls avocado white root rot disease caused by Rosellinia necatrix by using mechanisms involving competition for nutrients and niches. Here, a functional genomics approach was conducted to identify the bacterial traits involved in the interaction with this fungal pathogen. Our results contribute to a better understanding of the multitrophic interactions established among bacterial biocontrol agents, the plant rhizosphere, and the mycelia of soilborne pathogens.
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20
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Das S, Sreevidya VS, Udvadia AJ, Gyaneshwar P. Dopamine-induced sulfatase and its regulator are required for Salmonella enterica serovar Typhimurium pathogenesis. MICROBIOLOGY-SGM 2019; 165:302-310. [PMID: 30648943 DOI: 10.1099/mic.0.000769] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Catecholamine hormones enhance the virulence of pathogenic bacteria. Studies in the 1980s made intriguing observations that catecholamines were required for induction of sulfatase activity in many enteric pathogens, including Salmonella enterica serovar Typhimurium. In this report, we show that STM3122 and STM3124, part of horizontally acquired Salmonella pathogenesis island 13, encode a catecholamine-induced sulfatase and its regulator, respectively. Induction of sulfatase activity was independent of the well-studied QseBC and QseEF two-component regulatory systems. S. Typhimurium 14028S mutants lacking STM3122 or STM3124 showed reduced virulence in zebrafish. Because catecholamines are inactivated by sulfation in the mammalian gut, S. Typhimurium could utilize CA-induced sulfatase to access free catecholamines for growth and virulence.
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Affiliation(s)
- Seema Das
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | | | - Ava J Udvadia
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Prasad Gyaneshwar
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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21
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Elder JR, Paul NC, Burin R, Guard J, Shah DH. Genomic organization and role of SPI-13 in nutritional fitness of Salmonella. Int J Med Microbiol 2018; 308:1043-1052. [PMID: 30466554 DOI: 10.1016/j.ijmm.2018.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/21/2018] [Accepted: 10/10/2018] [Indexed: 02/07/2023] Open
Abstract
Salmonella pathogenicity island 13 (SPI-13) contributes to the virulence of Salmonella. The majority of the SPI-13 genes encode proteins putatively involved in bacterial metabolism, however, their functions largely remain uncharacterized. It is currently unknown if SPI-13 contributes to metabolic fitness of Salmonella and, if so, what are the metabolic substrates for the protein encoded by genes within SPI-13. We employed Phenotype Microarray (Biolog, USA) to compare the metabolic properties of SPI-13 deficient mutant (ΔSPI-13) and the WT parent strain of non-typhoidal Salmonella enterica sub sp. enterica serovar Enteritidis (S. Enteritidis). The results of Phenotype Microarray revealed that SPI-13 is required for efficient utilization of two micronutrients, namely, d-glucuronic acid (DGA) and tyramine (TYR), as sole sources of carbon and/or nitrogen. By systematic deletion of the individual gene(s), we identified specific genes within SPI-13 that are required for efficient utilization of DGA (SEN2977-80) and TYR (SEN2967 and SEN2971-72) as sole nutrient sources. The results show that SPI-13 mediated DGA and TYR metabolic pathways afford nutritional fitness to S. Enteritidis. Comparative genomics analysis of the SPI-13 locus from 247 Salmonella strains belonging to 57 different serovars revealed that SPI-13 genes specifically involved in the metabolism of DGA and TYR are highly conserved in Salmonella enterica. Because DGA and TYR are naturally present as metabolic byproducts in the gastrointestinal tract and other host tissues, we propose a metabolic model that shows that the role of SPI-13 mediated DGA and TYR metabolism in the nutritional fitness of Salmonella is likely linked to nutritional virulence of this pathogen.
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Affiliation(s)
- Jacob R Elder
- Department of Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, 99164-7040, USA
| | - Narayan C Paul
- Department of Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, 99164-7040, USA
| | - Raquel Burin
- Department of Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, 99164-7040, USA
| | - Jean Guard
- Egg Quality and Safety Research Unit, Agriculture Research Service, United StatesDepartment of Agriculture, Athens, GA, 30605, USA
| | - Devendra H Shah
- Department of Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, 99164-7040, USA; Paul Allen School for Global Animal Health, College of Veterinary Medicine, Washington State University, Pullman, Washington, 99164-7040, USA.
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22
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Zhou Z, Lundstrøm I, Tran-Dien A, Duchêne S, Alikhan NF, Sergeant MJ, Langridge G, Fotakis AK, Nair S, Stenøien HK, Hamre SS, Casjens S, Christophersen A, Quince C, Thomson NR, Weill FX, Ho SYW, Gilbert MTP, Achtman M. Pan-genome Analysis of Ancient and Modern Salmonella enterica Demonstrates Genomic Stability of the Invasive Para C Lineage for Millennia. Curr Biol 2018; 28:2420-2428.e10. [PMID: 30033331 PMCID: PMC6089836 DOI: 10.1016/j.cub.2018.05.058] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 02/09/2018] [Accepted: 05/18/2018] [Indexed: 02/04/2023]
Abstract
Salmonella enterica serovar Paratyphi C causes enteric (paratyphoid) fever in humans. Its presentation can range from asymptomatic infections of the blood stream to gastrointestinal or urinary tract infection or even a fatal septicemia [1]. Paratyphi C is very rare in Europe and North America except for occasional travelers from South and East Asia or Africa, where the disease is more common [2, 3]. However, early 20th-century observations in Eastern Europe [3, 4] suggest that Paratyphi C enteric fever may once have had a wide-ranging impact on human societies. Here, we describe a draft Paratyphi C genome (Ragna) recovered from the 800-year-old skeleton (SK152) of a young woman in Trondheim, Norway. Paratyphi C sequences were recovered from her teeth and bones, suggesting that she died of enteric fever and demonstrating that these bacteria have long caused invasive salmonellosis in Europeans. Comparative analyses against modern Salmonella genome sequences revealed that Paratyphi C is a clade within the Para C lineage, which also includes serovars Choleraesuis, Typhisuis, and Lomita. Although Paratyphi C only infects humans, Choleraesuis causes septicemia in pigs and boar [5] (and occasionally humans), and Typhisuis causes epidemic swine salmonellosis (chronic paratyphoid) in domestic pigs [2, 3]. These different host specificities likely evolved in Europe over the last ∼4,000 years since the time of their most recent common ancestor (tMRCA) and are possibly associated with the differential acquisitions of two genomic islands, SPI-6 and SPI-7. The tMRCAs of these bacterial clades coincide with the timing of pig domestication in Europe [6]. Salmonella enterica aDNA sequences were found within 800-year-old teeth and bone The invasive Para C lineage was defined from 50,000 modern S. enterica genomes The Para C lineage includes Ragna, the aDNA genome, and human and swine pathogens Only few genomic changes occurred in the Para C lineage over its 3,000-year history
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Affiliation(s)
- Zhemin Zhou
- Warwick Medical School, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK.
| | - Inge Lundstrøm
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen, Denmark
| | - Alicia Tran-Dien
- Unité des Bactéries Pathogènes Entériques, Institut Pasteur, Paris, France
| | - Sebastián Duchêne
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Nabil-Fareed Alikhan
- Warwick Medical School, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - Martin J Sergeant
- Warwick Medical School, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | | | - Anna K Fotakis
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen, Denmark
| | | | | | - Stian S Hamre
- Department of Archaeology, History, Cultural Studies and Religion, University of Bergen, Post Box 7805, 5020 Bergen, Norway
| | - Sherwood Casjens
- Pathology Department, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | | | - Christopher Quince
- Warwick Medical School, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | | | | | - Simon Y W Ho
- School of Life and Environmental Sciences; University of Sydney, Sydney NSW 2006, Australia
| | - M Thomas P Gilbert
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen, Denmark; NTNU University Museum, N-7491 Trondheim, Norway.
| | - Mark Achtman
- Warwick Medical School, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK.
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23
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Panzenhagen PHN, Cabral CC, Suffys PN, Franco RM, Rodrigues DP, Conte-Junior CA. Comparative genome analysis and characterization of the Salmonella Typhimurium strain CCRJ_26 isolated from swine carcasses using whole-genome sequencing approach. Lett Appl Microbiol 2018; 66:352-359. [PMID: 29397031 DOI: 10.1111/lam.12859] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/11/2018] [Accepted: 01/20/2018] [Indexed: 02/03/2023]
Abstract
Salmonella pathogenicity relies on virulence factors many of which are clustered within the Salmonella pathogenicity islands. Salmonella also harbours mobile genetic elements such as virulence plasmids, prophage-like elements and antimicrobial resistance genes which can contribute to increase its pathogenicity. Here, we have genetically characterized a selected S. Typhimurium strain (CCRJ_26) from our previous study with Multiple Drugs Resistant profile and high-frequency PFGE clonal profile which apparently persists in the pork production centre of Rio de Janeiro State, Brazil. By whole-genome sequencing, we described the strain's genome virulent content and characterized the repertoire of bacterial plasmids, antibiotic resistance genes and prophage-like elements. Here, we have shown evidence that strain CCRJ_26 genome possible represent a virulence-associated phenotype which may be potentially virulent in human infection. SIGNIFICANCE AND IMPACT OF THE STUDY Whole-genome sequencing technologies are still costly and remain underexplored for applied microbiology in Brazil. Hence, this genomic description of S. Typhimurium strain CCRJ_26 will provide help in future molecular epidemiological studies. The analysis described here reveals a quick and useful pipeline for bacterial virulence characterization using whole-genome sequencing approach.
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Affiliation(s)
- P H N Panzenhagen
- Food Science Program, Chemistry Institute, University Federal of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.,Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil
| | - C C Cabral
- Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil.,Faculty of Veterinary Medicine, Severino Sombra University (USS), Vassouras, Rio de Janeiro, Brazil
| | - P N Suffys
- Laboratory of Molecular Biology and Diagnosis of Infectious Diseases, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - R M Franco
- Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil
| | - D P Rodrigues
- National Reference Laboratory Diagnosis of Enteric Bacteria, Oswaldo Cruz Institute, Rio de Janeiro, Brazil
| | - C A Conte-Junior
- Food Science Program, Chemistry Institute, University Federal of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.,Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil.,National Institute of Quality Control in Health, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
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24
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Comparative genomics identifies distinct lineages of S. Enteritidis from Queensland, Australia. PLoS One 2018; 13:e0191042. [PMID: 29338017 PMCID: PMC5770046 DOI: 10.1371/journal.pone.0191042] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/27/2017] [Indexed: 11/19/2022] Open
Abstract
Salmonella enterica is a major cause of gastroenteritis and foodborne illness in Australia where notification rates in the state of Queensland are the highest in the country. S. Enteritidis is among the five most common serotypes reported in Queensland and it is a priority for epidemiological surveillance due to concerns regarding its emergence in Australia. Using whole genome sequencing, we have analysed the genomic epidemiology of 217 S. Enteritidis isolates from Queensland, and observed that they fall into three distinct clades, which we have differentiated as Clades A, B and C. Phage types and MLST sequence types differed between the clades and comparative genomic analysis has shown that each has a unique profile of prophage and genomic islands. Several of the phage regions present in the S. Enteritidis reference strain P125109 were absent in Clades A and C, and these clades also had difference in the presence of pathogenicity islands, containing complete SPI-6 and SPI-19 regions, while P125109 does not. Antimicrobial resistance markers were found in 39 isolates, all but one of which belonged to Clade B. Phylogenetic analysis of the Queensland isolates in the context of 170 international strains showed that Queensland Clade B isolates group together with the previously identified global clade, while the other two clades are distinct and appear largely restricted to Australia. Locally sourced environmental isolates included in this analysis all belonged to Clades A and C, which is consistent with the theory that these clades are a source of locally acquired infection, while Clade B isolates are mostly travel related.
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25
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Muyyarikkandy MS, Amalaradjou MA. Lactobacillus bulgaricus, Lactobacillus rhamnosus and Lactobacillus paracasei Attenuate Salmonella Enteritidis, Salmonella Heidelberg and Salmonella Typhimurium Colonization and Virulence Gene Expression In Vitro. Int J Mol Sci 2017; 18:E2381. [PMID: 29120368 PMCID: PMC5713350 DOI: 10.3390/ijms18112381] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/01/2017] [Accepted: 11/06/2017] [Indexed: 02/06/2023] Open
Abstract
Salmonella Enteritidis (SE), Salmonella Typhimurium (ST), and Salmonella Heidelberg (SH) have been responsible for numerous outbreaks associated with the consumption of poultry meat and eggs. Salmonella colonization in chicken is characterized by initial attachment to the cecal epithelial cells (CEC) followed by dissemination to the liver, spleen, and oviduct. Since cecal colonization is critical to Salmonella transmission along the food chain continuum, reducing this intestinal association could potentially decrease poultry meat and egg contamination. Hence, this study investigated the efficacy of Lactobacillus delbreuckii sub species bulgaricus (NRRL B548; LD), Lactobacillus paracasei (DUP-13076; LP), and Lactobacillus rhamnosus (NRRL B442; LR) in reducing SE, ST, and SH colonization in CEC and survival in chicken macrophages. Additionally, their effect on expression of Salmonella virulence genes essential for cecal colonization and survival in macrophages was evaluated. All three probiotics significantly reduced Salmonella adhesion and invasion in CEC and survival in chicken macrophages (p < 0.05). Further, the probiotic treatment led to a significant reduction in Salmonella virulence gene expression (p < 0.05). Results of the study indicate that LD, LP, and LR could potentially be used to control SE, ST, and SH colonization in chicken. However, these observations warrant further in vivo validation.
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26
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Signal transduction pathway mediated by the novel regulator LoiA for low oxygen tension induced Salmonella Typhimurium invasion. PLoS Pathog 2017; 13:e1006429. [PMID: 28575106 PMCID: PMC5476282 DOI: 10.1371/journal.ppat.1006429] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 06/19/2017] [Accepted: 05/23/2017] [Indexed: 02/03/2023] Open
Abstract
Salmonella enterica serovar Typhimurium (S. Typhimurium) is a major intestinal pathogen of both humans and animals. Salmonella pathogenicity island 1 (SPI-1)-encoded virulence genes are required for S. Typhimurium invasion. While oxygen (O2) limitation is an important signal for SPI-1 induction under host conditions, how the signal is received and integrated to the central SPI-1 regulatory system in S. Typhimurium is not clear. Here, we report a signal transduction pathway that activates SPI-1 expression in response to low O2. A novel regulator encoded within SPI-14 (STM14_1008), named LoiA (low oxygen induced factor A), directly binds to the promoter and activates transcription of hilD, leading to the activation of hilA (the master activator of SPI-1). Deletion of loiA significantly decreased the transcription of hilA, hilD and other representative SPI-1 genes (sipB, spaO, invH, prgH and invF) under low O2 conditions. The response of LoiA to the low O2 signal is mediated by the ArcB/ArcA two-component system. Deletion of either arcA or arcB significantly decreased transcription of loiA under low O2 conditions. We also confirmed that SPI-14 contributes to S. Typhimurium virulence by affecting invasion, and that loiA is the virulence determinant of SPI-14. Mice infection assays showed that S. Typhimurium virulence was severely attenuated by deletion of either the entire SPI-14 region or the single loiA gene after oral infection, while the virulence was not affected by either deletion after intraperitoneal infection. The signal transduction pathway described represents an important mechanism for S. Typhimurium to sense and respond to low O2 conditions of the host intestinal tract for invasion. SPI-14-encoded loiA is an essential element of this pathway that integrates the low O2 signal into the SPI-1 regulatory system. Acquisition of SPI-14 is therefore crucial for the evolution of S. Typhimurium as an intestinal pathogen. Salmonella enterica serovar Typhimurium (S. Typhimurium) is a major intestinal pathogen of both humans and animals. Salmonella pathogenicity island 1 (SPI-1) is required for host cell invasion by S. Typhimurium. Expression of SPI-1 genes is induced by low oxygen (O2) tension under host conditions, but the relevant regulatory mechanisms are not clear. Here, we report a low O2-induced signal transduction pathway for the activation of SPI-1 expression in S. Typhimurium. A novel regulator, STM14_1008 (named LoiA), encoded within SPI-14 directly activates hilD, which in turn activates hilA (the master activator of SPI-1), and thus other SPI-1 genes under O2-limited conditions. The response of LoiA to the low O2 signal is mediated by the ArcB/ArcA two-component system. We also confirmed that SPI-14 contributes to S. Typhimurium virulence by affecting invasion, with loiA as the virulence determinant. This novel SPI-1 activation pathway can be used by S. Typhimurium to sense and respond to low O2 conditions of the host intestinal tract for invasion. Acquisition of SPI-14 is therefore very important for the evolution of S. Typhimurium virulence by providing an essential component of this pathway, loiA.
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27
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Espinoza RA, Silva-Valenzuela CA, Amaya FA, Urrutia ÍM, Contreras I, Santiviago CA. Differential roles for pathogenicity islands SPI-13 and SPI-8 in the interaction of Salmonella Enteritidis and Salmonella Typhi with murine and human macrophages. Biol Res 2017; 50:5. [PMID: 28202086 PMCID: PMC5311848 DOI: 10.1186/s40659-017-0109-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 02/04/2017] [Indexed: 02/03/2023] Open
Abstract
Background Salmonella pathogenicity island (SPI)-13 is conserved in many serovars of S. enterica, including S. Enteritidis, S. Typhimurium and S. Gallinarum. However, it is absent in typhoid serovars such as S. Typhi and Paratyphi A, which carry SPI-8 at the same genomic location. Because the interaction with macrophages is a critical step in Salmonella pathogenicity, in this study we investigated the role played by SPI-13 and SPI-8 in the interaction of S. Enteritidis and S. Typhi with cultured murine (RAW264.7) and human (THP-1) macrophages. Results
Our results showed that SPI-13 was required for internalization of S. Enteritidis in murine but not human macrophages. On the other hand, SPI-8 was not required for the interaction of S. Typhi with human or murine macrophages. Of note, the presence of an intact copy of SPI-13 in a S. Typhi mutant carrying a deletion of SPI-8 did not improve its ability to be internalized by, or survive in human or murine macrophages. Conclusions Altogether, our results point out to different roles for SPI-13 and SPI-8 during Salmonella infection. While SPI-13 contributes to the interaction of S. Enteritidis with murine macrophages, SPI-8 is not required in the interaction of S. Typhi with murine or human macrophages. We hypothesized that typhoid serovars have lost SPI-13 and maintained SPI-8 to improve their fitness during another phase of human infection. Electronic supplementary material The online version of this article (doi:10.1186/s40659-017-0109-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rodrigo A Espinoza
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago, Chile
| | - Cecilia A Silva-Valenzuela
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago, Chile.,Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Fernando A Amaya
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago, Chile
| | - Ítalo M Urrutia
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago, Chile
| | - Inés Contreras
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago, Chile.
| | - Carlos A Santiviago
- Laboratorio de Microbiología, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, Santiago, Chile.
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Elder JR, Chiok KL, Paul NC, Haldorson G, Guard J, Shah DH. The Salmonella pathogenicity island 13 contributes to pathogenesis in streptomycin pre-treated mice but not in day-old chickens. Gut Pathog 2016; 8:16. [PMID: 27141235 PMCID: PMC4852409 DOI: 10.1186/s13099-016-0098-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 04/03/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Salmonella enterica serovar Enteritidis (S. Enteritidis) is a human and animal pathogen that causes gastroenteritis characterized by inflammatory diarrhea and occasionally an invasive systemic infection. Salmonella pathogenicity islands (SPIs) are horizontally acquired genomic segments known to contribute to Salmonella pathogenesis. The objective of the current study was to determine the contribution of SPI-13 to S. Enteritidis pathogenesis. METHODS We deleted the entire SPI-13 (∆SPI-13) from the genome of S. Enteritidis CDC_2010K_0968 strain isolated from a human patient during the 2010 egg-associated outbreak in the US. The kinetics of infection of the wild-type parent and the ∆SPI-13 were compared in orally challenged day-old chickens and streptomycin pre-treated mice. The degree of intestinal inflammation and the survival of mutant strain within the avian (HD11) and murine (RAW264.7) macrophages were also determined. RESULTS The deletion of the SPI-13 resulted in impaired infection kinetics of S. Enteritidis in streptomycin pre-treated mice which was characterized by significantly lower (P < 0.05) viable counts in the ceca, liver and spleen, impaired ability to induce intestinal inflammation and reduced survival within murine macrophages. Conversely, there were no significant differences in the infection kinetics of ∆SPI-13 in day-old chickens in any of the organs tested and the survival of ∆SPI-13 within chicken macrophages remained unaltered. CONCLUSIONS The results of this study show that SPI-13 contributes to the pathogenesis of S. Enteritidis in streptomycin pre-treated mice but not in day-old chickens and raises the possibility that SPI-13 may play a role in pathogenesis and the host adaptation/restriction of Salmonella serovars.
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Affiliation(s)
- Jacob R Elder
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040 USA
| | - Kim Lam Chiok
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040 USA
| | - Narayan C Paul
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040 USA
| | - Gary Haldorson
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040 USA
| | - Jean Guard
- Egg Quality and Safety Research Unit, Agriculture Research Service, United States Department of Agriculture, Athens, GA 30605 USA
| | - Devendra H Shah
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040 USA ; Paul Allen School for Global Animal Health, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040 USA
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Srikumar S, Kröger C, Hébrard M, Colgan A, Owen SV, Sivasankaran SK, Cameron ADS, Hokamp K, Hinton JCD. RNA-seq Brings New Insights to the Intra-Macrophage Transcriptome of Salmonella Typhimurium. PLoS Pathog 2015; 11:e1005262. [PMID: 26561851 PMCID: PMC4643027 DOI: 10.1371/journal.ppat.1005262] [Citation(s) in RCA: 167] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 10/17/2015] [Indexed: 11/18/2022] Open
Abstract
Salmonella enterica serovar Typhimurium is arguably the world’s best-understood bacterial pathogen. However, crucial details about the genetic programs used by the bacterium to survive and replicate in macrophages have remained obscure because of the challenge of studying gene expression of intracellular pathogens during infection. Here, we report the use of deep sequencing (RNA-seq) to reveal the transcriptional architecture and gene activity of Salmonella during infection of murine macrophages, providing new insights into the strategies used by the pathogen to survive in a bactericidal immune cell. We characterized 3583 transcriptional start sites that are active within macrophages, and highlight 11 of these as candidates for the delivery of heterologous antigens from Salmonella vaccine strains. A majority (88%) of the 280 S. Typhimurium sRNAs were expressed inside macrophages, and SPI13 and SPI2 were the most highly expressed pathogenicity islands. We identified 31 S. Typhimurium genes that were strongly up-regulated inside macrophages but expressed at very low levels during in vitro growth. The SalComMac online resource allows the visualisation of every transcript expressed during bacterial replication within mammalian cells. This primary transcriptome of intra-macrophage S.-Typhimurium describes the transcriptional start sites and the transcripts responsible for virulence traits, and catalogues the sRNAs that may play a role in the regulation of gene expression during infection. The burden of Salmonellosis remains unacceptably high throughout the world and control measures have had limited success. Because Salmonella bacteria can be transmitted from the wider environment to animals and humans, the bacteria encounter diverse environments that include food, water, plant surfaces and the extracellular and intracellular phases of infection of eukaryotic hosts. An intricate transcriptional network has evolved to respond to a variety of environmental signals and control the “right time/ right place” expression of virulence genes. To understand how transcription is rewired during intracellular infection, we determined the primary transcriptome of Salmonella enterica serovar Typhimurium within murine macrophages. We report the coding genes, sRNAs and transcriptional start sites that are expressed within macrophages at 8 hours after infection, and use these to infer gene function. We identified gene promoters that are specifically expressed within macrophages and could drive the intracellular delivery of antigens by S. Typhimurium vaccine strains. These data contribute to our understanding of the mechanisms used by Salmonella to regulate virulence gene expression whilst replicating inside mammalian cells.
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Affiliation(s)
- Shabarinath Srikumar
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Carsten Kröger
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Magali Hébrard
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
| | - Aoife Colgan
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
| | - Siân V. Owen
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Sathesh K. Sivasankaran
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
| | | | - Karsten Hokamp
- Department of Genetics, School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College, Dublin, Ireland
| | - Jay C. D. Hinton
- Department of Microbiology, School of Genetics and Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin, Ireland
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- * E-mail:
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Dawoud TM, Jiang T, Mandal RK, Ricke SC, Kwon YM. Improving the efficiency of transposon mutagenesis in Salmonella enteritidis by overcoming host-restriction barriers. Mol Biotechnol 2015; 56:1004-10. [PMID: 24973023 DOI: 10.1007/s12033-014-9779-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Transposon mutagenesis using transposome complex is a powerful method for functional genomics analysis in diverse bacteria by creating a large number of random mutants to prepare a genome-saturating mutant library. However, strong host restriction barriers can lead to limitations with species- or strain-specific restriction-modification systems. The purpose of this study was to enhance the transposon mutagenesis efficiency of Salmonella Enteritidis to generate a larger number of random insertion mutants. Host-adapted Tn5 DNA was used to form a transposome complex, and this simple approach significantly and consistently improved the efficiency of transposon mutagenesis, resulting in a 46-fold increase in the efficiency as compared to non-adapted transposon DNA fragments. Random nature of Tn5 insertions was confirmed by high-throughput sequencing of the Tn5-junction sequences. The result based on S. Enteritidis in this study should find broad applications in preparing a comprehensive mutant library of other species using transposome complex.
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Affiliation(s)
- Turki M Dawoud
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, 72701, USA,
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Abstract
A dataset of bacterial diversity found in mites was compiled from 193 publications (from 1964 to January 2015). A total of 143 mite species belonging to the 3 orders (Mesostigmata, Sarcoptiformes and Trombidiformes) were recorded and found to be associated with approximately 150 bacteria species (in 85 genera, 51 families, 25 orders and 7 phyla). From the literature, the intracellular symbiont Cardinium, the scrub typhus agent Orientia, and Wolbachia (the most prevalent symbiont of arthropods) were the dominant mite-associated bacteria, with approximately 30 mite species infected each. Moreover, a number of bacteria of medical and veterinary importance were also reported from mites, including species from the genera Rickettsia, Anaplasma, Bartonella, Francisella, Coxiella, Borrelia, Salmonella, Erysipelothrix and Serratia. Significant differences in bacterial infection patterns among mite taxa were identified. These data will not only be useful for raising awareness of the potential for mites to transmit disease, but also enable a deeper understanding of the relationship of symbionts with their arthropod hosts, and may facilitate the development of intervention tools for disease vector control. This review provides a comprehensive overview of mite-associated bacteria and is a valuable reference database for future research on mites of agricultural, veterinary and/or medical importance.
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Wiedemann A, Virlogeux-Payant I, Chaussé AM, Schikora A, Velge P. Interactions of Salmonella with animals and plants. Front Microbiol 2015; 5:791. [PMID: 25653644 PMCID: PMC4301013 DOI: 10.3389/fmicb.2014.00791] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 12/22/2014] [Indexed: 12/16/2022] Open
Abstract
Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections.
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Affiliation(s)
- Agnès Wiedemann
- Institut National de la Recherche Agronomique, UMR1282 Infectiologie et Santé Publique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais Tours, France
| | - Isabelle Virlogeux-Payant
- Institut National de la Recherche Agronomique, UMR1282 Infectiologie et Santé Publique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais Tours, France
| | - Anne-Marie Chaussé
- Institut National de la Recherche Agronomique, UMR1282 Infectiologie et Santé Publique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais Tours, France
| | - Adam Schikora
- Institute for Phytopathology, Research Center for BioSystems, Land Use and Nutrition (IFZ), Justus Liebig University Giessen Giessen, Germany
| | - Philippe Velge
- Institut National de la Recherche Agronomique, UMR1282 Infectiologie et Santé Publique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais Tours, France
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Chakraborty S, Gogoi M, Chakravortty D. Lactoylglutathione lyase, a critical enzyme in methylglyoxal detoxification, contributes to survival of Salmonella in the nutrient rich environment. Virulence 2015; 6:50-65. [PMID: 25517857 PMCID: PMC4603430 DOI: 10.4161/21505594.2014.983791] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 10/29/2014] [Accepted: 10/31/2014] [Indexed: 02/02/2023] Open
Abstract
Glyoxalase I which is synonymously known as lactoylglutathione lyase is a critical enzyme in methylglyoxal (MG) detoxification. We assessed the STM3117 encoded lactoylglutathione lyase (Lgl) of Salmonella Typhimurium, which is known to function as a virulence factor, due in part to its ability to detoxify methylglyoxal. We found that STM3117 encoded Lgl isomerises the hemithioacetal adduct of MG and glutathione (GSH) into S-lactoylglutathione. Lgl was observed to be an outer membrane bound protein with maximum expression at the exponential growth phase. The deletion mutant of S. Typhimurium (Δlgl) exhibited a notable growth inhibition coupled with oxidative DNA damage and membrane disruptions, in accordance with the growth arrest phenomenon associated with typical glyoxalase I deletion. However, growth in glucose minimal medium did not result in any inhibition. Endogenous expression of recombinant Lgl in serovar Typhi led to an increased resistance and growth in presence of external MG. Being a metalloprotein, Lgl was found to get activated maximally by Co(2+) ion followed by Ni(2+), while Zn(2+) did not activate the enzyme and this could be attributed to the geometry of the particular protein-metal complex attained in the catalytically active state. Our results offer an insight on the pivotal role of the virulence associated and horizontally acquired STM3117 gene in non-typhoidal serovars with direct correlation of its activity in lending survival advantage to Salmonella spp.
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Affiliation(s)
- Sangeeta Chakraborty
- Department of Microbiology and Cell Biology; Indian Institute of Science; Bangalore, India
| | - Mayuri Gogoi
- Department of Microbiology and Cell Biology; Indian Institute of Science; Bangalore, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology; Indian Institute of Science; Bangalore, India
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Identification of novel factors involved in modulating motility of Salmonella enterica serotype typhimurium. PLoS One 2014. [PMID: 25369209 DOI: 10.1371/journal.pone.0111513.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Salmonella enterica serotype Typhimurium can move through liquid using swimming motility, and across a surface by swarming motility. We generated a library of targeted deletion mutants in Salmonella Typhimurium strain ATCC14028, primarily in genes specific to Salmonella, that we have previously described. In the work presented here, we screened each individual mutant from this library for the ability to move away from the site of inoculation on swimming and swarming motility agar. Mutants in genes previously described as important for motility, such as flgF, motA, cheY are do not move away from the site of inoculation on plates in our screens, validating our approach. Mutants in 130 genes, not previously known to be involved in motility, had altered movement of at least one type, 9 mutants were severely impaired for both types of motility, while 33 mutants appeared defective on swimming motility plates but not swarming motility plates, and 49 mutants had reduced ability to move on swarming agar but not swimming agar. Finally, 39 mutants were determined to be hypermotile in at least one of the types of motility tested. Both mutants that appeared non-motile and hypermotile on plates were assayed for expression levels of FliC and FljB on the bacterial surface and many of them had altered levels of these proteins. The phenotypes we report are the first phenotypes ever assigned to 74 of these open reading frames, as they are annotated as 'hypothetical genes' in the Typhimurium genome.
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Bogomolnaya LM, Aldrich L, Ragoza Y, Talamantes M, Andrews KD, McClelland M, Andrews-Polymenis HL. Identification of novel factors involved in modulating motility of Salmonella enterica serotype typhimurium. PLoS One 2014; 9:e111513. [PMID: 25369209 PMCID: PMC4219756 DOI: 10.1371/journal.pone.0111513] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 09/28/2014] [Indexed: 12/03/2022] Open
Abstract
Salmonella enterica serotype Typhimurium can move through liquid using swimming motility, and across a surface by swarming motility. We generated a library of targeted deletion mutants in Salmonella Typhimurium strain ATCC14028, primarily in genes specific to Salmonella, that we have previously described. In the work presented here, we screened each individual mutant from this library for the ability to move away from the site of inoculation on swimming and swarming motility agar. Mutants in genes previously described as important for motility, such as flgF, motA, cheY are do not move away from the site of inoculation on plates in our screens, validating our approach. Mutants in 130 genes, not previously known to be involved in motility, had altered movement of at least one type, 9 mutants were severely impaired for both types of motility, while 33 mutants appeared defective on swimming motility plates but not swarming motility plates, and 49 mutants had reduced ability to move on swarming agar but not swimming agar. Finally, 39 mutants were determined to be hypermotile in at least one of the types of motility tested. Both mutants that appeared non-motile and hypermotile on plates were assayed for expression levels of FliC and FljB on the bacterial surface and many of them had altered levels of these proteins. The phenotypes we report are the first phenotypes ever assigned to 74 of these open reading frames, as they are annotated as ‘hypothetical genes’ in the Typhimurium genome.
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Affiliation(s)
- Lydia M. Bogomolnaya
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, Texas, United States of America
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Lindsay Aldrich
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, Texas, United States of America
| | - Yuri Ragoza
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, Texas, United States of America
| | - Marissa Talamantes
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, Texas, United States of America
| | - Katharine D. Andrews
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, Texas, United States of America
| | - Michael McClelland
- Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, California, United States of America
| | - Helene L. Andrews-Polymenis
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, Texas, United States of America
- * E-mail:
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Chakraborty S, Chaudhuri D, Balakrishnan A, Chakravortty D. Salmonella methylglyoxal detoxification by STM3117-encoded lactoylglutathione lyase affects virulence in coordination with Salmonella pathogenicity island 2 and phagosomal acidification. MICROBIOLOGY-SGM 2014; 160:1999-2017. [PMID: 24961952 DOI: 10.1099/mic.0.078998-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Intracellular pathogens such as Salmonella enterica serovar Typhimurium (S. Typhimurium) manipulate their host cells through the interplay of various virulence factors. A multitude of such virulence factors are encoded on the genome of S. Typhimurium and are usually organized in pathogenicity islands. The virulence-associated genomic stretch of STM3117-3120 has structural features of pathogenicity islands and is present exclusively in non-typhoidal serovars of Salmonella. It encodes metabolic enzymes predicted to be involved in methylglyoxal metabolism. STM3117-encoded lactoylglutathione lyase significantly impacts the proliferation of intracellular Salmonella. The deletion mutant of STM3117 (Δlgl) fails to grow in epithelial cells but hyper-replicates in macrophages. This difference in proliferation outcome was the consequence of failure to detoxify methylglyoxal by Δlgl, which was also reflected in the form of oxidative DNA damage and upregulation of kefB in the mutant. Within macrophages, the toxicity of methylglyoxal adducts elicits the potassium efflux channel (KefB) in the mutant which subsequently modulates the acidification of mutant-containing vacuoles (MCVs). The perturbation in the pH of the MCV milieu and bacterial cytosol enhances the Salmonella pathogenicity island 2 translocation in Δlgl, increasing its net growth within macrophages. In epithelial cells, however, the maturation of Δlgl-containing vacuoles were affected as these non-phagocytic cells maintain less acidic vacuoles compared to those in macrophages. Remarkably, ectopic expression of Toll-like receptors 2 and 4 on epithelial cells partially restored the survival of Δlgl. This study identified a novel metabolic enzyme in S. Typhimurium whose activity during intracellular infection within a given host cell type differentially affected the virulence of the bacteria.
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Affiliation(s)
- Sangeeta Chakraborty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Debalina Chaudhuri
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Arjun Balakrishnan
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
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Bachmann NL, Petty NK, Ben Zakour NL, Szubert JM, Savill J, Beatson SA. Genome analysis and CRISPR typing of Salmonella enterica serovar Virchow. BMC Genomics 2014; 15:389. [PMID: 24885207 PMCID: PMC4042001 DOI: 10.1186/1471-2164-15-389] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 05/02/2014] [Indexed: 12/11/2022] Open
Abstract
Background Salmonella enterica subsp. enterica serovar Virchow has been recognized as a significant health burden in Asia, Australia and Europe. In addition to its global distribution, S. Virchow is clinically significant due to the frequency at which it causes invasive infections and its association with outbreaks arising from food-borne transmission. Here, we examine the genome of an invasive isolate of S. Virchow SVQ1 (phage type 8) from an outbreak in southeast Queensland, Australia. In addition to identifying new potential genotyping targets that could be used for discriminating between S. Virchow strains in outbreak scenarios, we also aimed to carry out a comprehensive comparative analysis of the S. Virchow genomes. Results Genome comparisons between S. Virchow SVQ1 and S. Virchow SL491, a previously published strain, identified a high degree of genomic similarity between the two strains with fewer than 200 single nucleotide differences. Clustered Regularly Interspaced Palindromic Repeats (CRISPR) regions were identified as a highly variable region that could be used to discriminate between S. Virchow isolates. We amplified and sequenced the CRISPR regions of fifteen S. Virchow isolates collected from seven different outbreaks across Australia. We observed three allelic types of the CRISPR region from these isolates based on the presence/absence of the spacers and were able to discriminate S. Virchow phage type 8 isolates originating from different outbreaks. A comparison with 27 published Salmonella genomes found that the S. Virchow SVQ1 genome encodes 11 previously described Salmonella Pathogenicity Islands (SPI), as well as additional genomic islands including a remnant integrative conjugative element that is distinct from SPI-7. In addition, the S. Virchow genome possesses a novel prophage that encodes the Type III secretion system effector protein SopE, a key Salmonella virulence factor. The prophage shares very little similarity to the SopE prophages found in other Salmonella serovars suggesting an independent acquisition of sopE. Conclusions The availability of this genome will serve as a genome template and facilitate further studies on understanding the virulence and global distribution of the S. Virchow serovar, as well as the development of genotyping methods for outbreak investigations. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-389) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | - John Savill
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia.
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Virulence determinants of Salmonella Gallinarum biovar Pullorum identified by PCR signature-tagged mutagenesis and the spiC mutant as a candidate live attenuated vaccine. Vet Microbiol 2014; 168:388-94. [DOI: 10.1016/j.vetmic.2013.11.024] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 11/13/2013] [Accepted: 11/15/2013] [Indexed: 11/16/2022]
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Bronowski C, Fookes MC, Gilderthorp R, Ashelford KE, Harris SR, Phiri A, Hall N, Gordon MA, Wain J, Hart CA, Wigley P, Thomson NR, Winstanley C. Genomic characterisation of invasive non-typhoidal Salmonella enterica Subspecies enterica Serovar Bovismorbificans isolates from Malawi. PLoS Negl Trop Dis 2013; 7:e2557. [PMID: 24244782 PMCID: PMC3828162 DOI: 10.1371/journal.pntd.0002557] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 10/11/2013] [Indexed: 11/18/2022] Open
Abstract
Background Invasive Non-typhoidal Salmonella (iNTS) are an important cause of bacteraemia in children and HIV-infected adults in sub-Saharan Africa. Previous research has shown that iNTS strains exhibit a pattern of gene loss that resembles that of host adapted serovars such as Salmonella Typhi and Paratyphi A. Salmonella enterica serovar Bovismorbificans was a common serovar in Malawi between 1997 and 2004. Methodology We sequenced the genomes of 14 Malawian bacteraemia and four veterinary isolates from the UK, to identify genomic variations and signs of host adaptation in the Malawian strains. Principal Findings Whole genome phylogeny of invasive and veterinary S. Bovismorbificans isolates showed that the isolates are highly related, belonging to the most common international S. Bovismorbificans Sequence Type, ST142, in contrast to the findings for S. Typhimurium, where a distinct Sequence Type, ST313, is associated with invasive disease in sub-Saharan Africa. Although genome degradation through pseudogene formation was observed in ST142 isolates, there were no clear overlaps with the patterns of gene loss seen in iNTS ST313 isolates previously described from Malawi, and no clear distinction between S. Bovismorbificans isolates from Malawi and the UK. The only defining differences between S. Bovismorbificans bacteraemia and veterinary isolates were prophage-related regions and the carriage of a S. Bovismorbificans virulence plasmid (pVIRBov). Conclusions iNTS S. Bovismorbificans isolates, unlike iNTS S. Typhiumrium isolates, are only distinguished from those circulating elsewhere by differences in the mobile genome. It is likely that these strains have entered a susceptible population and are able to take advantage of this niche. There are tentative signs of convergent evolution to a more human adapted iNTS variant. Considering its importance in causing disease in this region, S. Bovismorbificans may be at the beginning of this process, providing a reference against which to compare changes that may become fixed in future lineages in sub-Saharan Africa. Bacteraemia and meningitis caused by non-typhoidal Salmonella (including serovars Typhimurium, Enteritidis and Bovismorbificans) are a serious health issue in sub-Saharan Africa, particularly in young children and HIV-infected adults. Previous work has indicated that a distinct S. Typhimurium sequence type, ST313, has evolved and spread in these countries, and may be more human-adapted than isolates found in the developed world. We therefore investigated the genomes of Salmonella enterica serovar Bovismorbificans bacteraemia isolates from Malawi and compared them to genomes of veterinary S. Bovismorbificans isolates from the UK using Next Generation Sequencing Technology and subsequent genomic comparisons to establish if there is a genetic basis for this increase in invasive disease observed among African NTS. Contrary to the previous findings for S. Typhimurium, where a distinct ST is found only in sub-Saharan Africa, we discovered that the S. Bovismorbificans isolates from Malawi belong to the most common ST of the serovar and the genome is highly conserved across all sequenced isolates. The major differences between UK veterinary and African human isolates were due to prophage regions inserted into the genomes of African isolates, coupled with a higher prevalence of a virulence plasmid compared to the UK isolates.
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Affiliation(s)
- Christina Bronowski
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Maria C. Fookes
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Ruth Gilderthorp
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Kevin E. Ashelford
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Simon R. Harris
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Amos Phiri
- Malawi-Liverpool-Wellcome Trust Clinical Research Program, Queen Elizabeth Hospital, Blantyre, Malawi
| | - Neil Hall
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Melita A. Gordon
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- Malawi-Liverpool-Wellcome Trust Clinical Research Program, Queen Elizabeth Hospital, Blantyre, Malawi
- Department of Medicine, College of Medicine, University of Malawi, Malawi
| | - John Wain
- Department of Medical Microbiology, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Charles A. Hart
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Paul Wigley
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Nicholas R. Thomson
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
- * E-mail:
| | - Craig Winstanley
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
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Hammarlöf DL, Canals R, Hinton JCD. The FUN of identifying gene function in bacterial pathogens; insights from Salmonella functional genomics. Curr Opin Microbiol 2013; 16:643-51. [PMID: 24021902 DOI: 10.1016/j.mib.2013.07.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 07/12/2013] [Indexed: 02/01/2023]
Abstract
The availability of thousands of genome sequences of bacterial pathogens poses a particular challenge because each genome contains hundreds of genes of unknown function (FUN). How can we easily discover which FUN genes encode important virulence factors? One solution is to combine two different functional genomic approaches. First, transcriptomics identifies bacterial FUN genes that show differential expression during the process of mammalian infection. Second, global mutagenesis identifies individual FUN genes that the pathogen requires to cause disease. The intersection of these datasets can reveal a small set of candidate genes most likely to encode novel virulence attributes. We demonstrate this approach with the Salmonella infection model, and propose that a similar strategy could be used for other bacterial pathogens.
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Affiliation(s)
- Disa L Hammarlöf
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom
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Hayward MR, Jansen VAA, Woodward MJ. Comparative genomics of Salmonella enterica serovars Derby and Mbandaka, two prevalent serovars associated with different livestock species in the UK. BMC Genomics 2013; 14:365. [PMID: 23725633 PMCID: PMC3680342 DOI: 10.1186/1471-2164-14-365] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/27/2013] [Indexed: 01/06/2023] Open
Abstract
Background Despite the frequent isolation of Salmonella enterica sub. enterica serovars Derby and Mbandaka from livestock in the UK and USA little is known about the biological processes maintaining their prevalence. Statistics for Salmonella isolations from livestock production in the UK show that S. Derby is most commonly associated with pigs and turkeys and S. Mbandaka with cattle and chickens. Here we compare the first sequenced genomes of S. Derby and S. Mbandaka as a basis for further analysis of the potential host adaptations that contribute to their distinct host species distributions. Results Comparative functional genomics using the RAST annotation system showed that predominantly mechanisms that relate to metabolite utilisation, in vivo and ex vivo persistence and pathogenesis distinguish S. Derby from S. Mbandaka. Alignment of the genome nucleotide sequences of S. Derby D1 and D2 and S. Mbandaka M1 and M2 with Salmonella pathogenicity islands (SPI) identified unique complements of genes associated with host adaptation. We also describe a new genomic island with a putative role in pathogenesis, SPI-23. SPI-23 is present in several S. enterica serovars, including S. Agona, S. Dublin and S. Gallinarum, it is absent in its entirety from S. Mbandaka. Conclusions We discovered a new 37 Kb genomic island, SPI-23, in the chromosome sequence of S. Derby, encoding 42 ORFS, ten of which are putative TTSS effector proteins. We infer from full-genome synonymous SNP analysis that these two serovars diverged, between 182kya and 625kya coinciding with the divergence of domestic pigs. The differences between the genomes of these serovars suggest they have been exposed to different stresses including, phage, transposons and prolonged externalisation. The two serovars possess distinct complements of metabolic genes; many of which cluster into pathways for catabolism of carbon sources.
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Affiliation(s)
- Matthew R Hayward
- Animal Health and Veterinary Laboratories Agency, Woodham Lane, New Haw, Addlestone, Surrey, UK.
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Chaudhuri RR, Morgan E, Peters SE, Pleasance SJ, Hudson DL, Davies HM, Wang J, van Diemen PM, Buckley AM, Bowen AJ, Pullinger GD, Turner DJ, Langridge GC, Turner AK, Parkhill J, Charles IG, Maskell DJ, Stevens MP. Comprehensive assignment of roles for Salmonella typhimurium genes in intestinal colonization of food-producing animals. PLoS Genet 2013; 9:e1003456. [PMID: 23637626 PMCID: PMC3630085 DOI: 10.1371/journal.pgen.1003456] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Accepted: 03/02/2013] [Indexed: 11/19/2022] Open
Abstract
Chickens, pigs, and cattle are key reservoirs of Salmonella enterica, a foodborne pathogen of worldwide importance. Though a decade has elapsed since publication of the first Salmonella genome, thousands of genes remain of hypothetical or unknown function, and the basis of colonization of reservoir hosts is ill-defined. Moreover, previous surveys of the role of Salmonella genes in vivo have focused on systemic virulence in murine typhoid models, and the genetic basis of intestinal persistence and thus zoonotic transmission have received little study. We therefore screened pools of random insertion mutants of S. enterica serovar Typhimurium in chickens, pigs, and cattle by transposon-directed insertion-site sequencing (TraDIS). The identity and relative fitness in each host of 7,702 mutants was simultaneously assigned by massively parallel sequencing of transposon-flanking regions. Phenotypes were assigned to 2,715 different genes, providing a phenotype–genotype map of unprecedented resolution. The data are self-consistent in that multiple independent mutations in a given gene or pathway were observed to exert a similar fitness cost. Phenotypes were further validated by screening defined null mutants in chickens. Our data indicate that a core set of genes is required for infection of all three host species, and smaller sets of genes may mediate persistence in specific hosts. By assigning roles to thousands of Salmonella genes in key reservoir hosts, our data facilitate systems approaches to understand pathogenesis and the rational design of novel cross-protective vaccines and inhibitors. Moreover, by simultaneously assigning the genotype and phenotype of over 90% of mutants screened in complex pools, our data establish TraDIS as a powerful tool to apply rich functional annotation to microbial genomes with minimal animal use. Salmonella Typhimurium is a major cause of human diarrhoeal infections, usually acquired from chickens, pigs, cattle, or their products. To understand the basis of persistence and pathogenesis in these reservoir hosts, and to inform the design of novel vaccines and treatments, we generated a library of 7,702 S. Typhimurium mutants, each bearing an insertion at a random position in the genome. Using DNA sequencing, we identified the disrupted gene in each mutant and determined its relative abundance in a laboratory culture and after experimental infection of mice, chickens, pigs, and cattle. The method allowed large numbers of mutants to be investigated simultaneously, drastically reducing the number of animals required to perform a comprehensive screen. We identified mutants that grow in culture but do not survive in one or more of the animals. The genes disrupted in these mutants are inferred to be important for the infection process. Most of these genes were required in all three food-producing animals, but smaller subsets of genes may mediate persistence in a specific host species. The data provide the most comprehensive map of virulence-associated genes for any bacterial pathogen in natural hosts and are highly relevant for the design of control strategies.
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Affiliation(s)
- Roy R. Chaudhuri
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Eirwen Morgan
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Sarah E. Peters
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Stephen J. Pleasance
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Debra L. Hudson
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Holly M. Davies
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Jinhong Wang
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Pauline M. van Diemen
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Anthony M. Buckley
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Alison J. Bowen
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Gillian D. Pullinger
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
| | - Daniel J. Turner
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Gemma C. Langridge
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - A. Keith Turner
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Julian Parkhill
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Ian G. Charles
- The ithree institute, University of Technology Sydney, Broadway, Australia
| | - Duncan J. Maskell
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
| | - Mark P. Stevens
- Enteric Bacterial Pathogens Laboratory, Institute for Animal Health, Compton, Berkshire, United Kingdom
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The type VI secretion system encoded in Salmonella pathogenicity island 19 is required for Salmonella enterica serotype Gallinarum survival within infected macrophages. Infect Immun 2013; 81:1207-20. [PMID: 23357385 DOI: 10.1128/iai.01165-12] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Salmonella enterica serotype Gallinarum is the causative agent of fowl typhoid, a disease characterized by high morbidity and mortality that causes major economic losses in poultry production. We have reported that S. Gallinarum harbors a type VI secretion system (T6SS) encoded in Salmonella pathogenicity island 19 (SPI-19) that is required for efficient colonization of chicks. In the present study, we aimed to characterize the SPI-19 T6SS functionality and to investigate the mechanisms behind the phenotypes previously observed in vivo. Expression analyses revealed that SPI-19 T6SS core components are expressed and produced under in vitro bacterial growth conditions. However, secretion of the structural/secreted components Hcp1, Hcp2, and VgrG to the culture medium could not be determined, suggesting that additional signals are required for T6SS-dependent secretion of these proteins. In vitro bacterial competition assays failed to demonstrate a role for SPI-19 T6SS in interbacterial killing. In contrast, cell culture experiments with murine and avian macrophages (RAW264.7 and HD11, respectively) revealed production of a green fluorescent protein-tagged version of VgrG soon after Salmonella uptake. Furthermore, infection of RAW264.7 and HD11 macrophages with deletion mutants of SPI-19 or strains with genes encoding specific T6SS core components (clpV and vgrG) revealed that SPI-19 T6SS contributes to S. Gallinarum survival within macrophages at 20 h postuptake. SPI-19 T6SS function was not linked to Salmonella-induced cytotoxicity or cell death of infected macrophages, as has been described for other T6SS. Our data indicate that SPI-19 T6SS corresponds to a novel tool used by Salmonella to survive within host cells.
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Mitra A, Loh A, Gonzales A, Laniewski P, Willingham C, Curtiss Iii R, Roland KL. Safety and protective efficacy of live attenuated Salmonella Gallinarum mutants in Rhode Island Red chickens. Vaccine 2012; 31:1094-9. [PMID: 23261043 DOI: 10.1016/j.vaccine.2012.12.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 11/01/2012] [Accepted: 12/10/2012] [Indexed: 01/17/2023]
Abstract
Salmonella enterica serovar Gallinarum is the causative agent of fowl typhoid, an important systemic disease of poultry with economic consequences in developing nations. A live attenuated orally applied S. Gallinarum vaccine could provide a low cost method for controlling this disease. We constructed S. Gallinarum strains in which the expression of the crp, rfc and rfaH genes, important for virulence of Salmonella Typhimurium in mice, were under the control of an arabinose-regulated promoter. We evaluated the virulence of these strains compared to wild-type S. Gallinarum and to mutants carrying deletions in these genes. We found that rfc mutants were fully virulent, indicating that, unlike the S. Typhimurium mouse model, the rfc gene is dispensable in S. Gallinarum for virulence in birds. In the case of rfaH, the deletion mutant was attenuated and protective, while the strain with arabinose-regulated rfaH expression retained full virulence. The strain exhibiting arabinose-regulated crp expression was attenuated. Its virulence was not affected by the inclusion of 0.2% arabinose in the drinking water. Birds immunized with this strain were protected against a lethal S. Gallinarum challenge and against colonization with the human pathogen Salmonella Enteritidis. This work shows that an arabinose-regulated crp strain provides a basis for further development of a fowl typhoid vaccine.
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Affiliation(s)
- Arindam Mitra
- The Biodesign Institute, School of Life Sciences, Arizona State University, Tempe, AZ 85287, United States
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Periaswamy B, Maier L, Vishwakarma V, Slack E, Kremer M, Andrews-Polymenis HL, McClelland M, Grant AJ, Suar M, Hardt WD. Live attenuated S. Typhimurium vaccine with improved safety in immuno-compromised mice. PLoS One 2012; 7:e45433. [PMID: 23029007 PMCID: PMC3454430 DOI: 10.1371/journal.pone.0045433] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 08/17/2012] [Indexed: 12/23/2022] Open
Abstract
Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine's performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV). Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb−/−nos2−/− animals lacking NADPH oxidase and inducible NO synthase. In cybb−/−nos2−/− mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093), was >1000-fold attenuated in cybb−/−nos2−/− mice and ≈100 fold attenuated in tnfr1−/− animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA) response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety.
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Affiliation(s)
| | - Lisa Maier
- Institute of Microbiology, D-BIOL, ETH Zürich, Zürich, Switzerland
| | | | - Emma Slack
- Institute of Microbiology, D-BIOL, ETH Zürich, Zürich, Switzerland
| | | | | | - Michael McClelland
- The Vaccine Research Institute of San Diego, San Diego, California, United States of America
| | - Andrew J. Grant
- Department of Veterinary Medicine and Cambridge Infectious Diseases Consortium, University of Cambridge, Cambridge, United Kingdom
| | - Mrutyunjay Suar
- School of Biotechnology, KIIT University, Bhubaneswar, Odisha, India
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Transposon mutagenesis of Salmonella enterica serovar Enteritidis identifies genes that contribute to invasiveness in human and chicken cells and survival in egg albumen. Infect Immun 2012; 80:4203-15. [PMID: 22988017 DOI: 10.1128/iai.00790-12] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Salmonella enterica serovar Enteritidis is an important food-borne pathogen, and chickens are a primary reservoir of human infection. While most knowledge about Salmonella pathogenesis is based on research conducted on Salmonella enterica serovar Typhimurium, S. Enteritidis is known to have pathobiology specific to chickens that impacts epidemiology in humans. Therefore, more information is needed about S. Enteritidis pathobiology in comparison to that of S. Typhimurium. We used transposon mutagenesis to identify S. Enteritidis virulence genes by assay of invasiveness in human intestinal epithelial (Caco-2) cells and chicken liver (LMH) cells and survival within chicken (HD-11) macrophages as a surrogate marker for virulence. A total of 4,330 transposon insertion mutants of an invasive G1 Nal(r) strain were screened using Caco-2 cells. This led to the identification of attenuating mutations in a total of 33 different loci, many of which include genes previously known to contribute to enteric infection (e.g., Salmonella pathogenicity island 1 [SPI-1], SPI-4, SPI-5, CS54, fliH, fljB, csgB, spvR, and rfbMN) in S. Enteritidis and other Salmonella serovars. Several genes or genomic islands that have not been reported previously (e.g., SPI-14, ksgA, SEN0034, SEN2278, and SEN3503) or that are absent in S. Typhimurium or in most other Salmonella serovars (e.g., pegD, SEN1152, SEN1393, and SEN1966) were also identified. Most mutants with reduced Caco-2 cell invasiveness also showed significantly reduced invasiveness in chicken liver cells and impaired survival in chicken macrophages and in egg albumen. Consequently, these genes may play an important role during infection of the chicken host and also contribute to successful egg contamination by S. Enteritidis.
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López FE, de las Mercedes Pescaretti M, Morero R, Delgado MA. Salmonella Typhimurium general virulence factors: A battle of David against Goliath? Food Res Int 2012. [DOI: 10.1016/j.foodres.2011.08.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Cummins J, Gahan CG. Signature tagged mutagenesis in the functional genetic analysis of gastrointestinal pathogens. Gut Microbes 2012; 3:93-103. [PMID: 22555467 PMCID: PMC3370953 DOI: 10.4161/gmic.19578] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Signature tagged mutagenesis is a genetic approach that was developed to identify novel bacterial virulence factors. It is a negative selection method in which unique identification tags allow analysis of pools of mutants in mixed populations. The approach is particularly well suited to functional genetic analysis of the gastrointestinal phase of infection in foodborne pathogens and has the capacity to guide the development of novel vaccines and therapeutics. In this review we outline the technical principles underpinning signature-tagged mutagenesis as well as novel sequencing-based approaches for transposon mutant identification such as TraDIS (transposon directed insertion-site sequencing). We also provide an analysis of screens that have been performed in gastrointestinal pathogens which are a global health concern (Escherichia coli, Listeria monocytogenes, Helicobacter pylori, Vibrio cholerae and Salmonella enterica). The identification of key virulence loci through the use of signature tagged mutagenesis in mice and relevant larger animal models is discussed.
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Affiliation(s)
- Joanne Cummins
- Alimentary Pharmabiotic Centre; University College Cork; Cork, Ireland,Department of Microbiology; University College Cork; Cork, Ireland
| | - Cormac G.M. Gahan
- Alimentary Pharmabiotic Centre; University College Cork; Cork, Ireland,Department of Microbiology; University College Cork; Cork, Ireland,School of Pharmacy; University College Cork; Cork, Ireland,Correspondence to: Cormac G.M. Gahan,
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Genome scanning for conditionally essential genes in Salmonella enterica Serotype Typhimurium. Appl Environ Microbiol 2012; 78:3098-107. [PMID: 22367088 DOI: 10.1128/aem.06865-11] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
As more whole-genome sequences become available, there is an increasing demand for high-throughput methods that link genes to phenotypes, facilitating discovery of new gene functions. In this study, we describe a new version of the Tn-seq method involving a modified EZ:Tn5 transposon for genome-wide and quantitative mapping of all insertions in a complex mutant library utilizing massively parallel Illumina sequencing. This Tn-seq method was applied to a genome-saturating Salmonella enterica serotype Typhimurium mutant library recovered from selection under 3 different in vitro growth conditions (diluted Luria-Bertani [LB] medium, LB medium plus bile acid, and LB medium at 42°C), mimicking some aspects of host stressors. We identified an overlapping set of 105 protein-coding genes in S. Typhimurium that are conditionally essential under at least one of the above selective conditions. Competition assays using 4 deletion mutants (pyrD, glnL, recD, and STM14_5307) confirmed the phenotypes predicted by Tn-seq data, validating the utility of this approach in discovering new gene functions. With continuously increasing sequencing capacity of next generation sequencing technologies, this robust Tn-seq method will aid in revealing unexplored genetic determinants and the underlying mechanisms of various biological processes in Salmonella and the other approximately 70 bacterial species for which EZ:Tn5 mutagenesis has been established.
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