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Zhang Y, Liang S, Zhang S, Bai Q, Dai L, Wang J, Yao H, Zhang W, Liu G. Streptococcal arginine deiminase system defences macrophage bactericidal effect mediated by XRE family protein XtrSs. Virulence 2024; 15:2306719. [PMID: 38251714 PMCID: PMC10841013 DOI: 10.1080/21505594.2024.2306719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 01/12/2024] [Indexed: 01/23/2024] Open
Abstract
The arginine deiminase system (ADS) has been identified in various bacteria and functions to supplement energy production and enhance biological adaptability. The current understanding of the regulatory mechanism of ADS and its effect on bacterial pathogenesis is still limited. Here, we found that the XRE family transcriptional regulator XtrSs negatively affected Streptococcus suis virulence and significantly repressed ADS transcription when the bacteria were incubated in blood. Electrophoretic mobility shift (EMSA) and lacZ fusion assays further showed that XtrSs directly bind to the promoter of ArgR, an acknowledged positive regulator of bacterial ADS, to repress ArgR transcription. Moreover, we provided compelling evidence that S. suis could utilize arginine via ADS to adapt to acid stress, while ΔxtrSs enhanced this acid resistance by upregulating the ADS operon. Moreover, whole ADS-knockout S. suis increased arginine and antimicrobial NO in the infected macrophage cells, decreased intracellular survival, and even caused significant attenuation of bacterial virulence in a mouse infection model, while ΔxtrSs consistently presented the opposite results. Our experiments identified a novel ADS regulatory mechanism in S. suis, whereby XtrSs regulated ADS to modulate NO content in macrophages, promoting S. suis intracellular survival. Meanwhile, our findings provide a new perspective on how Streptococci evade the host's innate immune system.
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Affiliation(s)
- Yumin Zhang
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Song Liang
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Shidan Zhang
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Qiankun Bai
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Lei Dai
- Hainan Animal Disease Prevention and Control Center, Haikou, China
| | - Jinxiu Wang
- Hainan Animal Disease Prevention and Control Center, Haikou, China
| | - Huochun Yao
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Wei Zhang
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Guangjin Liu
- Sanya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Sanya, China
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- OIE Reference Lab for Swine Streptococcosis, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
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Zhu Y, Mou X, Song Y, Zhang Q, Sun B, Liu H, Tang H, Bao R. Molecular mechanism of the one-component regulator RccR on bacterial metabolism and virulence. Nucleic Acids Res 2024; 52:3433-3449. [PMID: 38477394 PMCID: PMC11014249 DOI: 10.1093/nar/gkae171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 02/22/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
The regulation of carbon metabolism and virulence is critical for the rapid adaptation of pathogenic bacteria to host conditions. In Pseudomonas aeruginosa, RccR is a transcriptional regulator of genes involved in primary carbon metabolism and is associated with bacterial resistance and virulence, although the exact mechanism is unclear. Our study demonstrates that PaRccR is a direct repressor of the transcriptional regulator genes mvaU and algU. Biochemical and structural analyses reveal that PaRccR can switch its DNA recognition mode through conformational changes triggered by KDPG binding or release. Mutagenesis and functional analysis underscore the significance of allosteric communication between the SIS domain and the DBD domain. Our findings suggest that, despite its overall structural similarity to other bacterial RpiR-type regulators, RccR displays a more complex regulatory element binding mode induced by ligands and a unique regulatory mechanism.
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Affiliation(s)
- Yibo Zhu
- Center of Infectious Diseases, Division of Infectious Diseases in State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Xingyu Mou
- Center of Infectious Diseases, Division of Infectious Diseases in State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yingjie Song
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Qianqian Zhang
- Centre for Artificial Intelligence Driven Drug Discovery, Faculty of Applied Sciences, Macao Polytechnic University, Macao 999078, China
| | - Bo Sun
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, China
| | - Huanxiang Liu
- Centre for Artificial Intelligence Driven Drug Discovery, Faculty of Applied Sciences, Macao Polytechnic University, Macao 999078, China
| | - Hong Tang
- Center of Infectious Diseases, Division of Infectious Diseases in State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
| | - Rui Bao
- Center of Infectious Diseases, Division of Infectious Diseases in State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China
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Quorum-Sensing Inhibition by Gram-Positive Bacteria. Microorganisms 2022; 10:microorganisms10020350. [PMID: 35208805 PMCID: PMC8875677 DOI: 10.3390/microorganisms10020350] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 12/01/2022] Open
Abstract
The modern paradigm assumes that interspecies communication of microorganisms occurs through precise regulatory mechanisms. In particular, antagonism between bacteria or bacteria and fungi can be achieved by direct destruction of the targeted cells through the regulated production of antimicrobial metabolites or by controlling their adaptive mechanisms, such as the formation of biofilms. The quorum-quenching phenomenon provides such a countermeasure strategy. This review discusses quorum-sensing suppression by Gram-positive microorganisms, the underlying mechanisms of this process, and its molecular intermediates. The main focus will be on Gram-positive bacteria that have practical applications, such as starter cultures for food fermentation, probiotics, and other microorganisms of biotechnological importance. The possible evolutionary role of quorum-quenching mechanisms during the development of interspecies interactions of bacteria is also considered. In addition, the review provides possible practical applications for these mechanisms, such as the control of pathogens, improving the efficiency of probiotics, and plant protection.
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Hu Q, Yao L, Liao X, Zhang LS, Li HT, Li TT, Jiang QG, Tan MF, Li L, Draheim RR, Huang Q, Zhou R. Comparative Phenotypic, Proteomic, and Phosphoproteomic Analysis Reveals Different Roles of Serine/Threonine Phosphatase and Kinase in the Growth, Cell Division, and Pathogenicity of Streptococcus suis. Microorganisms 2021; 9:microorganisms9122442. [PMID: 34946045 PMCID: PMC8707513 DOI: 10.3390/microorganisms9122442] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/22/2021] [Accepted: 11/22/2021] [Indexed: 11/24/2022] Open
Abstract
Eukaryote-like serine/threonine kinases (STKs) and cognate phosphatases (STPs) comprise an important regulatory system in many bacterial pathogens. The complexity of this regulatory system has not been fully understood due to the presence of multiple STKs/STPs in many bacteria and their multiple substrates involved in many different physiological and pathogenetic processes. Streptococci are the best materials for the study due to a single copy of the gene encoding STK and its cognate STP. Although several studies have been done to investigate the roles of STK and STP in zoonotic Streptococcus suis, respectively, few studies were performed on the coordinated regulatory roles of this system. In this study, we carried out a systemic study on STK/STP in S. suis by using a comparative phenotypic, proteomic, and phosphoproteomic analysis. Mouse infection assays revealed that STK played a much more important role in S. suis pathogenesis than STP. The ∆stk and ∆stp∆stk strains, but not ∆stp, showed severe growth retardation. Moreover, both ∆stp and ∆stk strains displayed defects in cell division, but they were abnormal in different ways. The comparative proteomics and phosphoproteomics revealed that deletion of stk or stp had a significant influence on protein expression. Interestingly, more virulence factors were found to be downregulated in ∆stk than ∆stp. In ∆stk strain, a substantial number of the proteins with a reduced phosphorylation level were involved in cell division, energy metabolism, and protein translation. However, only a few proteins showed increased phosphorylation in ∆stp, which also included some proteins related to cell division. Collectively, our results show that both STP and STK are critical regulatory proteins for S. suis and that STK seems to play more important roles in growth, cell division, and pathogenesis.
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Affiliation(s)
- Qiao Hu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Lun Yao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Xia Liao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Liang-Sheng Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Hao-Tian Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Ting-Ting Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Qing-Gen Jiang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
| | - Mei-Fang Tan
- Institute of Animal Husbandry and Veterinary Science, Jiangxi Academy of Agricultural Sciences, Nanchang 330200, China;
| | - Lu Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of China, Wuhan 430070, China
| | - Roger R. Draheim
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2UP, UK;
| | - Qi Huang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of China, Wuhan 430070, China
- Correspondence: (Q.H.); (R.Z.)
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Q.H.); (L.Y.); (X.L.); (L.-S.Z.); (H.-T.L.); (T.-T.L.); (Q.-G.J.); (L.L.)
- Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
- International Research Center for Animal Disease, Ministry of Science and Technology of China, Wuhan 430070, China
- Correspondence: (Q.H.); (R.Z.)
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Zhu H, Zhou J, Wang D, Yu Z, Li B, Ni Y, He K. Quantitative proteomic analysis reveals that serine/threonine kinase is involved in Streptococcus suis virulence and adaption to stress conditions. Arch Microbiol 2021; 203:4715-4726. [PMID: 34028569 PMCID: PMC8141825 DOI: 10.1007/s00203-021-02369-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 05/06/2021] [Accepted: 05/08/2021] [Indexed: 12/27/2022]
Abstract
The eukaryotic-type serine/threonine kinase of Streptococcus suis serotype 2 (SS2) performs critical roles in bacterial pathogenesis. In this study, isobaric tags for relative and absolute quantification (iTRAQ) MS/MS were used to analyze the protein profiles of wild type strain SS2-1 and its isogenic STK deletion mutant (Δstk). A total of 281 significant differential proteins, including 147 up-regulated and 134 down-regulated proteins, were found in Δstk. Moreover, 69 virulence factors (VFs) among these 281 proteins were predicted by the Virulence Factor Database (VFDB), including 38 downregulated and 31 up-regulated proteins in Δstk, among which 15 down regulated VFs were known VFs of SS2. Among the down-regulated proteins, high temperature requirement A (HtrA), glutamine synthase (GlnA), ferrichrome ABC transporter substrate-binding protein FepB, and Zinc-binding protein AdcA are known to be involved in bacterial survival and/or nutrient and energy acquisition under adverse host conditions. Overall, our results indicate that STK regulates the expression of proteins involved in virulence of SS2 and its adaption to stress environments.
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Affiliation(s)
- Haodan Zhu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China
| | - Junming Zhou
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China
| | - Dandan Wang
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China
| | - Zhengyu Yu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China
| | - Bin Li
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China
| | - Yanxiu Ni
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China.
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China.
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China.
| | - Kongwang He
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China.
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, People's Republic of China.
- Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, People's Republic of China.
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Guo G, Kong X, Du D, Wei D, Yu Y, Zhang W. Genome-wide association study identifies the virulence-associated marker in Streptococcus suis serotype 2. INFECTION GENETICS AND EVOLUTION 2021; 92:104894. [PMID: 33964473 DOI: 10.1016/j.meegid.2021.104894] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/29/2021] [Accepted: 05/03/2021] [Indexed: 12/15/2022]
Abstract
Streptococcus suis (S. suis) has been reported to be a highly invasive pathogen in swine, which causes severe infections like meningitis, arthritis and septicemia, and also a zoonotic agent for humans. Although many putative virulence factors (VFs) have been identified, the exact and wildly accepted virulence associated marker and pathogenesis mechanism of S. suis are still unclear. To establish connection of the genotypes with virulence phenotypes, we performed an "internal standard" method based on the zebrafish model to assess the virulence phenotypes of S. suis and did the genome-wide association study (GWAS) based on the genomes of 68 S. suis isolates. Through GWAS, a total number of 172 genes were identified. Among these genes, 143 of them distribute in virulent isolates. Further VFs interaction network analysis based on protein-protein interaction database found that 71 genes identified in this study could interact with known VFs and some of them even played an important role as the bridge between known VFs or formed important hub. In addition, 12 genes were found conserved in virulent isolates and 3 genes were conserved in avirulent isolates, 8 genes of the virulent conserved genes were belonging to a srtBCD pili cluster. Considering that sbp2', a member of the srtBCD pili cluster has been reported as a virulence-associated factor, we predict that sbp2' could be a fitness virulence-associated marker of virulent isolates. Taken together, our findings contribute to the insights in S. suis pathogenesis, enhance the knowledge of the genomic evolution of S. suis and provide several novel virulence-associated candidates.
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Affiliation(s)
- Genglin Guo
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China.
| | - Xuewei Kong
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Dechao Du
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China.
| | - Dan Wei
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China.
| | - Yanfei Yu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Veterinary Biological Engineering and Technology of Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Wei Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China.
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Tram G, Jennings MP, Blackall PJ, Atack JM. Streptococcus suis pathogenesis-A diverse array of virulence factors for a zoonotic lifestyle. Adv Microb Physiol 2021; 78:217-257. [PMID: 34147186 DOI: 10.1016/bs.ampbs.2020.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Streptococcus suis is a major cause of respiratory tract and invasive infections in pigs and is responsible for a substantial disease burden in the pig industry. S. suis is also a significant cause of bacterial meningitis in humans, particularly in South East Asia. S. suis expresses a wide array of virulence factors, and although many are described as being required for disease, no single factor has been demonstrated to be absolutely required. The lack of uniform distribution of known virulence factors among individual strains and lack of evidence that any particular virulence factor is essential for disease makes the development of vaccines and treatments challenging. Here we review the current understanding of S. suis virulence factors and their role in the pathogenesis of this important zoonotic pathogen.
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Affiliation(s)
- Greg Tram
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Michael P Jennings
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Patrick J Blackall
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, Australia
| | - John M Atack
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia.
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Screening of Virulence-Related Transcriptional Regulators in Streptococcus suis. Genes (Basel) 2020; 11:genes11090972. [PMID: 32825733 PMCID: PMC7564649 DOI: 10.3390/genes11090972] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 01/08/2023] Open
Abstract
Streptococcus suis (S.suis) is an important zoonotic pathogen that causes many severe diseases in pigs and humans. Virulence-related transcriptional regulators have been widely reported in pathogenic microorganisms, but only a few have been identified in S.suis. Our aim was to screen virulence-related transcriptional regulators in S.suis. A total of 89 such genes were predicted in the S.suis genome, of which 22 were up-regulated and 18 were down-regulated during S.suis infection in mice. To evaluate the roles of these differentially expressed factors in S.suis virulence, deletion mutants were constructed, and 10 mutants were successfully obtained. Among these genes, the deletion of comR, sitR, or sxvR caused significantly decreased virulence in mice, compared to that with the wild-type strain. Moreover, the survival of ΔcomR, ΔsitR, and ΔsxvR mutant strains in blood was significantly reduced both in vitro and in vivo. Furthermore, their pro-inflammatory abilities were also obviously decreased in vivo. The regulatory mechanisms of comR, sitR, and sxvR were then analyzed by whole transcriptome RNA sequencing (RNA-Seq). Results indicated that the absence of comR induced the down-regulation of 17 virulence factors or virulence-related factors, including genes involved in the synthesis of capsules, oxidative stress tolerance, immune evasion, and cell division. Furthermore, three and two virulence factors or virulence-related factors were down-regulated upon deletion of sitR and sxvR, respectively. Thus, this study reports the discovery of three virulence-associated transcriptional regulatory factors in S.suis. These factors could ultimately be targeted to control infection caused by these bacteria.
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Guo G, Du D, Yu Y, Zhang Y, Qian Y, Zhang W. Pan-genome analysis of Streptococcus suis serotype 2 revealed genomic diversity among strains of different virulence. Transbound Emerg Dis 2020; 68:637-647. [PMID: 32654396 DOI: 10.1111/tbed.13725] [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: 03/03/2020] [Revised: 06/26/2020] [Accepted: 07/06/2020] [Indexed: 12/13/2022]
Abstract
Streptococcus suis (SS) is an emerging zoonotic pathogen that causes severe infections in swine and humans. Among the 33 known serotypes, serotype 2 is most frequently associated with infections in pigs and humans. To better understand the virulence characterization of S. suis serotype 2 (SS2) and discriminate the difference between virulent and avirulent strains in SS2, characterization of the genomic features of strains with different virulence is required. The result showed that Streptococcus suis have an open pan-genome. The pan-genome shared by the 19 S. suis serotype 2 strains was composed of 1,239 core genes and 2,436 accessory genes. COG analysis indicated that core genes are involved in the basic physiological function, but accessory genes related to tachytely evolution. Comparative analysis between core genomes of virulent strains and 9 avirulent strains suggested that srtBCD pilus cluster was a significant discrepancy between virulent and avirulent strains. Analysis between high virulent and group B low virulent strains showed 53 and 58 genes specific to each other. Moreover, genomes of avirulent strains tend to be larger than virulent strains; avirulent strains tend to possess more prophages sequences than virulent strains. Our findings could be contributed to a better understanding of the genomics of S. suis serotype 2.
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Affiliation(s)
- Genglin Guo
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.,OIE Reference Lab for Swine Streptococcosis, Nanjing, China
| | - Dechao Du
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.,OIE Reference Lab for Swine Streptococcosis, Nanjing, China
| | - Yanfei Yu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.,OIE Reference Lab for Swine Streptococcosis, Nanjing, China.,Key Laboratory of Veterinary Biological Engineering and Technology of Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yuhang Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.,OIE Reference Lab for Swine Streptococcosis, Nanjing, China
| | - Yunyun Qian
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.,OIE Reference Lab for Swine Streptococcosis, Nanjing, China
| | - Wei Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.,OIE Reference Lab for Swine Streptococcosis, Nanjing, China
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10
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Zhao Y, Li G, Yao XY, Lu SG, Wang J, Shen XD, Li M. The Impact of SsPI-1 Deletion on Streptococcus suis Virulence. Pathogens 2019; 8:pathogens8040287. [PMID: 31817637 PMCID: PMC6963714 DOI: 10.3390/pathogens8040287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/03/2019] [Accepted: 12/04/2019] [Indexed: 01/26/2023] Open
Abstract
(1) Background: Streptococcus suis is an important zoonotic pathogen that infects pigs and can occasionally cause life-threatening systemic infections in humans. Two large-scale outbreaks of streptococcal toxic shock-like syndrome in China suggest that the pathogenicity of S. suis has been changing in recent years. Genetic analysis revealed the presence of a chromosomal pathogenicity island (PAI) designated SsPI-1 in Chinese epidemic S. suis strains. The purpose of this study is to define the role of SsPI-1 in the virulence of S. suis. (2) Methods: A SsPI-1 deletion mutant was compared to the wild-type strain regarding the ability to attach to epithelial cells, to cause host disease and mortality, and to stimulate host immune response in experimental infection of piglets. (3) Results: Deletion of SsPI-1 significantly reduces adherence of S. suis to epithelial cells and abolishes the lethality of the wild-type strain in piglets. The SsPI-1 mutant causes no significant pathological lesions and exhibits an impaired ability to induce proinflammatory cytokine production. (4) Conclusions: Deletion of the SsPI-1 PAI attenuates the virulence of this pathogen. We conclude that SsPI-1 is a critical contributor to the evolution of virulence in epidemic S. suis.
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Affiliation(s)
- Yan Zhao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing 400038, China; (Y.Z.); (G.L.); (S.-G.L.); (J.W.)
| | - Gang Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing 400038, China; (Y.Z.); (G.L.); (S.-G.L.); (J.W.)
| | - Xin-Yue Yao
- Jinling Hospital Research Institute of Clinical Laboratory Medicine, Nanjing University, School of Medicine, Nanjing 210002, China;
| | - Shu-Guang Lu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing 400038, China; (Y.Z.); (G.L.); (S.-G.L.); (J.W.)
| | - Jing Wang
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing 400038, China; (Y.Z.); (G.L.); (S.-G.L.); (J.W.)
| | - Xiao-Dong Shen
- Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
- Correspondence: (M.L.); (X.-D.S.); Tel.: +86-23-68772241 (M.L.)
| | - Ming Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing 400038, China; (Y.Z.); (G.L.); (S.-G.L.); (J.W.)
- Correspondence: (M.L.); (X.-D.S.); Tel.: +86-23-68772241 (M.L.)
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11
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A novel small RNA contributes to restrain cellular chain length and anti-phagocytic ability in Streptococcus suis 2. Microb Pathog 2019; 137:103730. [PMID: 31499182 DOI: 10.1016/j.micpath.2019.103730] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 02/04/2023]
Abstract
Streptococcus suis serotype 2 (SS2) is an important porcine and human pathogen. Regulatory small non-coding RNAs (sRNAs) play an essential role in diverse physiological processes, although they remain poorly understood in SS2. In this study, we identified eight novel sRNAs through a combination of computational strategies and experimental identification. To explore roles of these novel sRNAs, sRNA34 was preferentially selected to assess phenotypes of the deletion strain in vitro and in vivo. The inactivation of sRNA34 significantly elongated the cellular chain, remarkably increased sensitivity to phagocytosis by RAW264.7, and attenuated virulence in a mouse infection model. Transcriptomic analysis revealed that inactivation of sRNA34 altered expression of multiple genes contributing to cellular chain formation and elongation, indicating a potential mechanism of sRNA34 in maintaining proper bacterial chain length to resist phagocytosis by the host cell. In summary, sRNA34 is a novel sRNA that contributes to cellular chain regulation and the anti-phagocytosis ability of SS2.
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12
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Yehuda A, Slamti L, Malach E, Lereclus D, Hayouka Z. Elucidating the Hot Spot Residues of Quorum Sensing Peptidic Autoinducer PapR by Multiple Amino Acid Replacements. Front Microbiol 2019; 10:1246. [PMID: 31231335 PMCID: PMC6568020 DOI: 10.3389/fmicb.2019.01246] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/20/2019] [Indexed: 11/29/2022] Open
Abstract
The quorum sensing (QS) system of Bacillus cereus, an opportunistic human pathogen, utilizes the autoinducing PapR peptide signal that mediates the activation of the pleiotropic virulence regulator PlcR. A set of synthetic 7-mer PapR-derived peptides (PapR7; ADLPFEF) have been shown to inhibit efficiently the PlcR regulon activity and the production of virulence factors, reflected by a loss in hemolytic activity without affecting bacterial growth. Interestingly, these first potent synthetic inhibitors involved D-amino acid or alanine replacements of three amino acids; proline, glutamic acid, and phenylalanine of the heptapeptide PapR. To better understand the role of these three positions in PlcR activity, we report herein the second generation design, synthesis, and characterization of PapR7-derived combinations, alternate double and triple alanine and D-amino acids replacement at these positions. Our findings generate a new set of non-native PapR7-derived peptides that inhibit the PlcR regulon activity and the production of virulence factors. Using the amino acids substitution strategy, we revealed the role of proline and glutamic acid on PlcR regulon activation. Moreover, we demonstrated that the D-Glutamic acid substitution was crucial for the design of stronger PlcR antagonists. These peptides represent potent synthetic inhibitors of B. cereus QS and constitute new and readily accessible chemical tools for the study of the PlcR system. Our method might be applied to other quorum sensing systems to design new anti-virulence agents.
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Affiliation(s)
- Avishag Yehuda
- Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Leyla Slamti
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Einav Malach
- Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Didier Lereclus
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Zvi Hayouka
- Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
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13
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Co-regulation of CodY and (p)ppGpp synthetases on morphology and pathogenesis of Streptococcus suis. Microbiol Res 2019; 223-225:88-98. [PMID: 31178056 DOI: 10.1016/j.micres.2019.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 02/28/2019] [Accepted: 04/06/2019] [Indexed: 01/04/2023]
Abstract
CodY and (p)ppGpp synthetases are two important global regulators of bacteria. In some pathogens, such as Listeria monocytogenes, the GTP pool links these two regulatory systems, and introducing a codY mutant into the ΔrelA strain restored the pathogenicity of the attenuated ΔrelA mutant. In previous studies, we identified the (p)ppGpp synthetases (RelA and RelQ) and CodY of Streptococcus suis. To understand the interrelationships between these two regulators in S. suis, a ΔrelAΔrelQΔcodY mutant was constructed, and its growth, morphology, and pathogenicity were evaluated. Compared with ΔrelAΔrelQ, ΔcodY, its growth was very slow, but its chain length was partly restored to the wild-type length and its capsule became thick and rough. The adherence, invasion ability, and resistance to whole-blood killing in vitro of ΔrelAΔrelQΔcodY and its lethality and colonization ability in mice were clearly reduced, which differs from the effects of these mutations in L. monocytogenes. An analysis of gene expression showed that CodY interacted with the relA promoter in a GTP-independent manner to positively regulate the expression of relA. The introduction of a codY mutant into the ΔrelAΔrelQ strain further reduced the expression of virulence factors, which suggests a novel interaction between the (p)ppGpp synthetases and CodY. This study extends our understanding of the relationship between the (p)ppGpp-mediated stringent response and the regulation of CodY in S. suis.
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14
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Zhu H, Wang Y, Ni Y, Zhou J, Han L, Yu Z, Mao A, Wang D, Fan H, He K. The Redox-Sensing Regulator Rex Contributes to the Virulence and Oxidative Stress Response of Streptococcus suis Serotype 2. Front Cell Infect Microbiol 2018; 8:317. [PMID: 30280091 PMCID: PMC6154617 DOI: 10.3389/fcimb.2018.00317] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 08/20/2018] [Indexed: 01/06/2023] Open
Abstract
Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen responsible for septicemia and meningitis. The redox-sensing regulator Rex has been reported to play critical roles in the metabolism regulation, oxidative stress response, and virulence of various pathogens. In this study, we identified and characterized a Rex ortholog in the SS2 virulent strain SS2-1 that is involved in bacterial pathogenicity and stress environment susceptibility. Our data show that the Rex-knockout mutant strain Δrex exhibited impaired growth in medium with hydrogen peroxide or a low pH compared with the wildtype strain SS2-1 and the complementary strain CΔrex. In addition, Δrex showed a decreased level of survival in whole blood and in RAW264.7 macrophages. Further analyses revealed that Rex deficiency significantly attenuated bacterial virulence in an animal model. A comparative proteome analysis found that the expression levels of several proteins involved in virulence and oxidative stress were significantly different in Δrex compared with SS2-1. Electrophoretic mobility shift assays revealed that recombinant Rex specifically bound to the promoters of target genes in a manner that was modulated by NADH and NAD+. Taken together, our data suggest that Rex plays critical roles in the virulence and oxidative stress response of SS2.
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Affiliation(s)
- Haodan Zhu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China
| | - Yong Wang
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Yanxiu Ni
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China
| | - Junming Zhou
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China.,Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, China
| | - Lixiao Han
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Zhengyu Yu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China
| | - Aihua Mao
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China
| | - Dandan Wang
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China
| | - Hongjie Fan
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China.,College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Kongwang He
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China.,Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonose, Yangzhou University, Yangzhou, China.,Key Lab of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base, Nanjing, China
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15
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Chang P, Li W, Shi G, Li H, Yang X, Xia Z, Ren Y, Li Z, Chen H, Bei W. The VraSR regulatory system contributes to virulence in Streptococcus suis via resistance to innate immune defenses. Virulence 2018; 9:771-782. [PMID: 29471718 PMCID: PMC5955479 DOI: 10.1080/21505594.2018.1428519] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Streptococcus suis is a highly invasive pathogen that can cause sepsis and meningitis in pigs and humans. However, we have limited understanding of the mechanisms S. suis uses to evade innate immunity. To investigate the involvement of the two-component signal transduction system of S. suis in host immune defense, we examined the expression of 15 response regulators of S. suis following stimulation with polymorphonuclear leukocytes (PMNs). We found that several response regulators were significantly up-regulated including vraR. Thus, we constructed an isogenic deletion mutant of vraSR genes in S. suis and demonstrated VraSR promotes both bacterial survival in human blood and resistance to human PMN-mediated killing. The VraSR mutant was more susceptible to phagocytosis by human PMNs and had greater sensitivity to oxidant and lysozyme than wild-type S. suis. Furthermore, in vitro findings and in vivo evidence from a mouse infection model together strongly demonstrate that ΔvraSR had greatly attenuated virulence compared with wild-type S. suis. Collectively, our data reveal that VraSR is a critical regulatory system that contributes to the survival of S. suis and its ability to defend against host innate immunity.
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Affiliation(s)
- Peixi Chang
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China.,b Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center of Sustainable Pig Production , Huazhong Agricultural University , Wuhan , China
| | - Weitian Li
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China
| | - Guolin Shi
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China.,b Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center of Sustainable Pig Production , Huazhong Agricultural University , Wuhan , China
| | - Huan Li
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China.,b Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center of Sustainable Pig Production , Huazhong Agricultural University , Wuhan , China
| | - Xiaoqing Yang
- c Huazhong Agricultural University hospital , Huazhong Agricultural University , Wuhan , China
| | - Zechen Xia
- d College of Food Science and Technology , Huazhong Agricultural University , Wuhan , China
| | - Yuan Ren
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China
| | - Zhiwei Li
- d College of Food Science and Technology , Huazhong Agricultural University , Wuhan , China
| | - Huanchun Chen
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China.,b Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center of Sustainable Pig Production , Huazhong Agricultural University , Wuhan , China
| | - Weicheng Bei
- a State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine , Huazhong Agricultural University , Wuhan , China.,b Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center of Sustainable Pig Production , Huazhong Agricultural University , Wuhan , China
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16
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Yehuda A, Slamti L, Bochnik-Tamir R, Malach E, Lereclus D, Hayouka Z. Turning off Bacillus cereus quorum sensing system with peptidic analogs. Chem Commun (Camb) 2018; 54:9777-9780. [PMID: 30105347 DOI: 10.1039/c8cc05496g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We explored quenching of the PlcR-PapR quorum-sensing system in Bacillus cereus. We generated PapR7-peptidic derivatives that inhibit this system and thus the production of virulence factors, reflected by a loss in hemolytic activity, without affecting bacterial growth. To our knowledge, these peptides represent the first potent synthetic inhibitors of quorum-sensing in B. cereus.
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Affiliation(s)
- Avishag Yehuda
- Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, 76100, Israel.
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17
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Zheng C, Li L, Ge H, Meng H, Li Y, Bei W, Zhou X. Role of two-component regulatory systems in the virulence of Streptococcus suis. Microbiol Res 2018; 214:123-128. [PMID: 30031474 DOI: 10.1016/j.micres.2018.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/19/2018] [Accepted: 07/07/2018] [Indexed: 01/01/2023]
Abstract
Streptococcus suis is an important zoonotic pathogen that causes severe infections and great economic losses worldwide. Understanding how this pathogen senses and responds to environmental signals during the infectious process can offer insight into its pathogenesis and may be helpful in the development of drug targets. Two-component regulatory systems (TCSs) play an essential role in this environmental response. In S. suis, at least 15 groups of TCSs have been predicted. Among them, several have been demonstrated to be involved in virulence and/or stress response. In this review, we discuss the progress in the study of TCSs in S. suis, focusing on the role of these systems in the virulence of this bacterium.
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Affiliation(s)
- Chengkun Zheng
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety/Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China; State Key Laboratory of Agricultural Microbiology/The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Lingzhi Li
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety/Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Haojie Ge
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety/Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Hongmei Meng
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety/Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Yang Li
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety/Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China
| | - Weicheng Bei
- State Key Laboratory of Agricultural Microbiology/The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Xiaohui Zhou
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety/Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, The Ministry of Education of China, Yangzhou University, Yangzhou, 225009, China; Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, CT, 06269, USA.
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18
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Ni H, Fan W, Li C, Wu Q, Hou H, Hu D, Zheng F, Zhu X, Wang C, Cao X, Shao ZQ, Pan X. Streptococcus suis DivIVA Protein Is a Substrate of Ser/Thr Kinase STK and Involved in Cell Division Regulation. Front Cell Infect Microbiol 2018; 8:85. [PMID: 29616196 PMCID: PMC5869912 DOI: 10.3389/fcimb.2018.00085] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 03/02/2018] [Indexed: 12/14/2022] Open
Abstract
Streptococcus suis serotype 2 is an important swine pathogen and an emerging zoonotic agent that causes severe infections. Recent studies have reported a eukaryotic-like Ser/Thr protein kinase (STK) gene and characterized its role in the growth and virulence of different S. suis 2 strains. In the present study, phosphoproteomic analysis was adopted to identify substrates of the STK protein. Seven proteins that were annotated to participate in different cell processes were identified as potential substrates, which suggests the pleiotropic effects of stk on S. suis 2 by targeting multiple pathways. Among them, a protein characterized as cell division initiation protein (DivIVA) was further investigated. In vitro analysis demonstrated that the recombinant STK protein directly phosphorylates threonine at amino acid position 199 (Thr-199) of DivIVA. This effect could be completely abolished by the T199A mutation. To determine the specific role of DivIVA in growth and division, a divIVA mutant was constructed. The ΔdivIVA strain exhibited impaired growth and division, including lower viability, enlarged cell mass, asymmetrical division caused by aberrant septum, and extremely weak pathogenicity in a mouse infection model. Collectively, our results reveal that STK regulates the cell growth and virulence of S. suis 2 by targeting substrates that are involved in different biological pathways. The inactivation of DivIVA leads to severe defects in cell division and strongly attenuates pathogenicity, thereby indicating its potential as a molecular drug target against S. suis.
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Affiliation(s)
- Hua Ni
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China.,The Key Laboratory of Ecology and Biological Resources in Yarkand Oasis at Colleges and Universities Under the Department of Education of Xinjiang Uygur Autonomous Region, Kashgar University, Kashgar, China
| | - Weiwei Fan
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,Department of Pharmacy, Changzhou Wujin People's Hospital, Changzhou, China
| | - Chaolong Li
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Qianqian Wu
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Hongfen Hou
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Dan Hu
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Feng Zheng
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Xuhui Zhu
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Changjun Wang
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China
| | - Xiangrong Cao
- School of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Zhu-Qing Shao
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xiuzhen Pan
- Department of Microbiology, Hua Dong Research Institute for Medicine and Biotechnics, Nanjing, China.,School of Life Sciences, Nanjing Normal University, Nanjing, China
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19
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Functional characterization of murB-potABCD operon for polyamine uptake and peptidoglycan synthesis in Streptococcus suis. Microbiol Res 2018; 207:177-187. [DOI: 10.1016/j.micres.2017.11.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 10/11/2017] [Accepted: 11/12/2017] [Indexed: 01/27/2023]
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20
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Zhang C, Sun W, Tan M, Dong M, Liu W, Gao T, Li L, Xu Z, Zhou R. The Eukaryote-Like Serine/Threonine Kinase STK Regulates the Growth and Metabolism of Zoonotic Streptococcus suis. Front Cell Infect Microbiol 2017; 7:66. [PMID: 28326294 PMCID: PMC5339665 DOI: 10.3389/fcimb.2017.00066] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/21/2017] [Indexed: 12/21/2022] Open
Abstract
Like eukaryotes, bacteria express one or more serine/threonine kinases (STKs) that initiate diverse signaling networks. The STK from Streptococcus suis is encoded by a single-copy stk gene, which is crucial in stress response and virulence. To further understand the regulatory mechanism of STK in S. suis, a stk deletion strain (Δstk) and its complementary strain (CΔstk) were constructed to systematically decode STK characteristics by applying whole transcriptome RNA sequencing (RNA-Seq) and phosphoproteomic analysis. Numerous genes were differentially expressed in Δstk compared with the wild-type parental strain SC-19, including 320 up-regulated and 219 down-regulated genes. Particularly, 32 virulence-associated genes (VAGs) were significantly down-regulated in Δstk. Seven metabolic pathways relevant to bacterial central metabolism and translation are significantly repressed in Δstk. Phosphoproteomic analysis further identified 12 phosphoproteins that exhibit differential phosphorylation in Δstk. These proteins are associated with cell growth and division, glycolysis, and translation. Consistently, phenotypic assays confirmed that the Δstk strain displayed deficient growth and attenuated pathogenicity. Thus, STK is a central regulator that plays an important role in cell growth and division, as well as S. suis metabolism.
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Affiliation(s)
- Chunyan Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Wen Sun
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Meifang Tan
- Veterinary Medicine Laboratory, Institute of Animal Husbandry and Veterinary Medicine, Jiangxi Academy of Agricultural Sciences Nanchang, China
| | - Mengmeng Dong
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Wanquan Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Ting Gao
- Veterinary Medicine Laboratory, Institute of Animal Husbandry and Veterinary Science, Hubei Academy of Agricultural Sciences Wuhan, China
| | - Lu Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; Cooperative Innovation Center of Sustainable Pig ProductionWuhan, China
| | - Zhuofei Xu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; Cooperative Innovation Center of Sustainable Pig ProductionWuhan, China
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; Cooperative Innovation Center of Sustainable Pig ProductionWuhan, China
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21
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Critical Streptococcus suis Virulence Factors: Are They All Really Critical? Trends Microbiol 2017; 25:585-599. [PMID: 28274524 DOI: 10.1016/j.tim.2017.02.005] [Citation(s) in RCA: 167] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/30/2017] [Accepted: 02/09/2017] [Indexed: 01/15/2023]
Abstract
Streptococcus suis is an important swine pathogen that can be transmitted to humans by contact with diseased animals or contaminated raw pork products. This pathogen possesses a coat of capsular polysaccharide (CPS) that confers protection against the immune system. Yet, the CPS is not the only virulence factor enabling this bacterium to successfully colonize, invade, and disseminate in its host leading to severe systemic diseases such as meningitis and toxic shock-like syndrome. Indeed, recent research developments, cautiously inventoried in this review, have revealed over 100 'putative virulence factors or traits' (surface-associated or secreted components, regulatory genes or metabolic pathways), of which at least 37 have been claimed as being 'critical' for virulence. In this review we discuss the current contradictions and controversies raised by this explosion of virulence factors and the future directions that may be conceived to advance and enlighten research on S. suis pathogenesis.
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22
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Jiang X, Yang Y, Zhou J, Zhu L, Gu Y, Zhang X, Li X, Fang W. Roles of the Putative Type IV-like Secretion System Key Component VirD4 and PrsA in Pathogenesis of Streptococcus suis Type 2. Front Cell Infect Microbiol 2016; 6:172. [PMID: 27995095 PMCID: PMC5133265 DOI: 10.3389/fcimb.2016.00172] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 11/17/2016] [Indexed: 12/19/2022] Open
Abstract
Streptococcus suis type 2 (SS2) is a zoonotic pathogen causing septic infection, meningitis and pneumonia in pigs and humans. SS2 may cause streptococcal toxic shock syndrome (STSS) probably due to excessive release of inflammatory cytokines. A previous study indicated that the virD4 gene in the putative type IV-like secretion system (T4SS) within the 89K pathogenicity island specific for recent epidemic strains contributed to the development of STSS. However, the functional basis of VirD4 in STSS remains unclear. Here we show that deletion of virD4 led to reduced virulence as shown by about 65% higher LD50, lower bacterial load in liver and brain, and lower level of expression of inflammatory cytokines in mice and cell lines than its parent strain. The ΔVirD4 mutant was more easily phagocytosed, suggesting its role as an anti-phagocytic factor. Oxidative stress that mimic bacterial exposure to respiratory burst of phagocytes upregulated expression of virD4. Proteomic analysis identified 10 secreted proteins of significant differences between the parent and mutant strains under oxidative stress, including PrsA, a peptidyl-prolyl isomerase. The SS2 PrsA expressed in E. coli caused a dose-dependent cell death and increased expression of proinflammatory IL-1β, IL-6 and TNF-α in murine macrophage cells. Our data provide novel insights into the contribution of the VirD4 factor to STSS pathogenesis, possibly via its anti-phagocytic activity, upregulation of its expression upon oxidative stress and its involvement in increased secretion of PrsA as a cell death inducer and proinflammatory effector.
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Affiliation(s)
- Xiaowu Jiang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Yunkai Yang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Jingjing Zhou
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Lexin Zhu
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Yuanxing Gu
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Xiaoyan Zhang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Xiaoliang Li
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
| | - Weihuan Fang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Zhejiang, China
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23
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Talagas A, Fontaine L, Ledesma-Garca L, Mignolet J, Li de la Sierra-Gallay I, Lazar N, Aumont-Nicaise M, Federle MJ, Prehna G, Hols P, Nessler S. Structural Insights into Streptococcal Competence Regulation by the Cell-to-Cell Communication System ComRS. PLoS Pathog 2016; 12:e1005980. [PMID: 27907189 PMCID: PMC5131891 DOI: 10.1371/journal.ppat.1005980] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 10/04/2016] [Indexed: 11/19/2022] Open
Abstract
In Gram-positive bacteria, cell-to-cell communication mainly relies on extracellular signaling peptides, which elicit a response either indirectly, by triggering a two-component phosphorelay, or directly, by binding to cytoplasmic effectors. The latter comprise the RNPP family (Rgg and original regulators Rap, NprR, PrgX and PlcR), whose members regulate important bacterial processes such as sporulation, conjugation, and virulence. RNPP proteins are increasingly considered as interesting targets for the development of new antibacterial agents. These proteins are characterized by a TPR-type peptide-binding domain, and except for Rap proteins, also contain an N-terminal HTH-type DNA-binding domain and display a transcriptional activity. Here, we elucidate the structure-function relationship of the transcription factor ComR, a new member of the RNPP family, which positively controls competence for natural DNA transformation in streptococci. ComR is directly activated by the binding of its associated pheromone XIP, the mature form of the comX/sigX-inducing-peptide ComS. The crystal structure analysis of ComR from Streptococcus thermophilus combined with a mutational analysis and in vivo assays allows us to propose an original molecular mechanism of the ComR regulation mode. XIP-binding induces release of the sequestered HTH domain and ComR dimerization to allow DNA binding. Importantly, we bring evidence that this activation mechanism is conserved and specific to ComR orthologues, demonstrating that ComR is not an Rgg protein as initially proposed, but instead constitutes a new member of the RNPP family. In addition, identification of XIP and ComR residues important for competence activation constitutes a crucial step towards the design of antagonistic strategies to control gene exchanges among streptococci. Bacterial cell-cell communication systems are based on the secretion of signal molecules. These quorum-sensing systems allow bacteria to coordinate genes expression according to the density of their local population. In Gram-positive bacteria, intracellular quorum sensors regulated by re-internalized signal peptides control the expression of genes involved in essential bacterial processes such as horizontal gene transfer, biofilm formation, sporulation or virulence. In most streptococci, including pathogenic species, the ComR regulator and its cognate signal peptide ComS activate competence for natural DNA transformation, a major mechanism for horizontal gene transfer and antibiotic resistance acquisition. To elucidate the molecular mechanism of ComR activation, we performed the structure-function analysis of the ComRS system from S. thermophilus. We solved the crystal structures of the apo form of ComR and of the complex with XIP, the mature form of ComS, and DNA. We showed that peptide binding shifts the protein from an inactive monomeric state, characterized by the sequestration of the DNA-binding domain, to an active dimer. This idiosyncratic mechanism was confirmed by in vitro interaction measurements and in vivo transcription assays using ComR mutants and XIP variants. These results may be of special interest for the future design of new antimicrobials targeting antibiotic-resistant pathogens.
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Affiliation(s)
- Antoine Talagas
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Laetitia Fontaine
- Institute of Life Sciences (ISV), Biochemistry, Biophysics and Genetics of Microorganisms (BBGM), Université catholique de Louvain, Croix du Sud, 4-5 (L7.07.06), Louvain-La-Neuve, Belgium
| | - Laura Ledesma-Garca
- Institute of Life Sciences (ISV), Biochemistry, Biophysics and Genetics of Microorganisms (BBGM), Université catholique de Louvain, Croix du Sud, 4-5 (L7.07.06), Louvain-La-Neuve, Belgium
| | - Johann Mignolet
- Institute of Life Sciences (ISV), Biochemistry, Biophysics and Genetics of Microorganisms (BBGM), Université catholique de Louvain, Croix du Sud, 4-5 (L7.07.06), Louvain-La-Neuve, Belgium
| | - Inès Li de la Sierra-Gallay
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Noureddine Lazar
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Magali Aumont-Nicaise
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Michael J. Federle
- Dept. of Medicinal Chemistry and Pharmacognosy, Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Gerd Prehna
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Center for Structural Biology, Research Resources Center, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Pascal Hols
- Institute of Life Sciences (ISV), Biochemistry, Biophysics and Genetics of Microorganisms (BBGM), Université catholique de Louvain, Croix du Sud, 4-5 (L7.07.06), Louvain-La-Neuve, Belgium
- * E-mail: (PH); (SN)
| | - Sylvie Nessler
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
- * E-mail: (PH); (SN)
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24
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Segura M, Calzas C, Grenier D, Gottschalk M. Initial steps of the pathogenesis of the infection caused by Streptococcus suis: fighting against nonspecific defenses. FEBS Lett 2016; 590:3772-3799. [PMID: 27539145 DOI: 10.1002/1873-3468.12364] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 08/11/2016] [Accepted: 08/16/2016] [Indexed: 12/16/2022]
Abstract
Interactions between a bacterial pathogen and its potentially susceptible host are initiated with the colonization step. During respiratory/oral infection, the pathogens must compete with the normal microflora, resist defense mechanisms of the local mucosal immunity, and finally reach, adhere, and breach the mucosal epithelial cell barrier in order to induce invasive disease. This is the case during infection by the swine and zoonotic pathogen Streptococcus suis, which is able to counteract mucosal barriers to induce severe meningitis and sepsis in swine and in humans. The initial steps of the pathogenesis of S. suis infection has been a neglected area of research, overshadowed by studies on the systemic and central nervous phases of the disease. In this Review article, we provide for the first time, an exclusive focus on S. suis colonization and the potential mechanisms involved in S. suis establishment at the mucosa, as well as the mechanisms regulating mucosal barrier breakdown. The role of mucosal immunity is also addressed. Finally, we demystify the extensive list of putative adhesins and virulence factors reported to be involved in the initial steps of pathogenesis by S. suis.
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Affiliation(s)
- Mariela Segura
- Laboratory of Immunology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada.,Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - Cynthia Calzas
- Laboratory of Immunology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada.,Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Laboratory of Streptococcus suis, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Daniel Grenier
- Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Groupe de Recherche en Écologie Buccale (GREB), Faculté de Médecine Dentaire, Université Laval, Quebec City, Quebec, Canada
| | - Marcelo Gottschalk
- Swine and Poultry Infectious Diseases Research Centre (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada.,Laboratory of Streptococcus suis, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
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25
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Willemse N, Howell KJ, Weinert LA, Heuvelink A, Pannekoek Y, Wagenaar JA, Smith HE, van der Ende A, Schultsz C. An emerging zoonotic clone in the Netherlands provides clues to virulence and zoonotic potential of Streptococcus suis. Sci Rep 2016; 6:28984. [PMID: 27381348 PMCID: PMC4933891 DOI: 10.1038/srep28984] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 06/13/2016] [Indexed: 01/03/2023] Open
Abstract
Streptococcus suis is a zoonotic swine pathogen and a major public health concern in Asia, where it emerged as an important cause of bacterial meningitis in adults. While associated with food-borne transmission in Asia, zoonotic S. suis infections are mainly occupational hazards elsewhere. To identify genomic differences that can explain zoonotic potential, we compared whole genomes of 98 S. suis isolates from human patients and pigs with invasive disease in the Netherlands, and validated our observations with 18 complete and publicly available sequences. Zoonotic isolates have smaller genomes than non-zoonotic isolates, but contain more virulence factors. We identified a zoonotic S. suis clone that diverged from a non-zoonotic clone by means of gene loss, a capsule switch, and acquisition of a two-component signalling system in the late 19th century, when foreign pig breeds were introduced. Our results indicate that zoonotic potential of S. suis results from gene loss, recombination and horizontal gene transfer events.
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Affiliation(s)
- N. Willemse
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Global Health-Amsterdam Institute for Global Health and Development, Academic Medical Center, University of Amsterdam, 1105 BM Amsterdam, The Netherlands
| | - K. J. Howell
- Department of Paediatrics, School of Clinical Medicine, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - L. A. Weinert
- Department of Veterinary Medicine, School of Biological Sciences, University of Cambridge, Cambridge CB3 0ES, United Kingdom
| | - A. Heuvelink
- GD Animal Health, 7400 AA Deventer, The Netherlands
| | - Y. Pannekoek
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - J. A. Wagenaar
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
- Central Veterinary Institute part of Wageningen UR, 8221 RA Lelystad, The Netherlands
| | - H. E. Smith
- Central Veterinary Institute part of Wageningen UR, 8221 RA Lelystad, The Netherlands
| | - A. van der Ende
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- National Reference Laboratory of Bacterial Meningitis, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - C. Schultsz
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Global Health-Amsterdam Institute for Global Health and Development, Academic Medical Center, University of Amsterdam, 1105 BM Amsterdam, The Netherlands
- Oxford University Clinical Research Unit, Centre for Tropical Medicine, District 5, Ho Chi Minh City, Vietnam
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26
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Li M, Shao ZQ, Guo Y, Wang L, Hou T, Hu D, Zheng F, Tang J, Wang C, Feng Y, Gao J, Pan X. The type II histidine triad protein HtpsC is a novel adhesion with the involvement of Streptococcus suis virulence. Virulence 2016; 6:631-41. [PMID: 26151575 PMCID: PMC4720241 DOI: 10.1080/21505594.2015.1056971] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Streptococcal histidine triad proteins HTPs are widely distributed within the Streptococcus genus. Based on the phylogenetic relationship and domain composition, HTPs are classified into type I and type II subfamilies. Previous studies revealed that several pathogenic streptococci contain more than one htp gene. We found that the highly virulent strain of Streptococcus suis 2 (S. suis 2), 05ZYH33 encodes 3 HTPs, designated HtpsA (previously described as HtpS), HtpsB, and HtpsC. Among them, HtpsC is the only member that contains leucine-rich repeat (LRR) domains at the C-terminal. In this study, we demonstrated that the recombinant HtpsC could bind to 2 different components of human ECM complex laminin and fibronectin in vitro, suggesting that it is a novel adhesin of S. suis 2. Having constructed an htpsC mutant, we evaluated its role in the pathogenesis of the highly virulent S. suis 2 strain 05ZYH33. Our data showed that inactivation of htpsC significantly affected adherence of S. suis 2 to Hep-2 cells and shortened the survival of the bacteria in whole blood. Furthermore, deletion of htpsC significantly attenuated the virulence of S. suis 2 in mice. These results demonstrated that htpsC was involved in the pathogenesis of the highly virulent S. suis 2 strain 05ZYH33. In line with the observation, immunization with HtpsC significantly prolonged mice's survival after S. suis 05ZYH33 challenge, indicating its potential use in the vaccine development against S. suis.
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Affiliation(s)
- Min Li
- a School of Laboratory Medicine and Life Science ; Wenzhou Medical University ; Wenzhou , China.,b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
| | - Zhu-Qing Shao
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China.,c State Key Laboratory of Pharmaceutical Biotechnology ; School of Life Sciences ; Nanjing University ; Nanjing , China
| | - Yuqing Guo
- a School of Laboratory Medicine and Life Science ; Wenzhou Medical University ; Wenzhou , China.,b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
| | - Ling Wang
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China.,d School of Life Sciences ; Nanjing Normal University ; Nanjing , China
| | - Tianqing Hou
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
| | - Dan Hu
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
| | - Feng Zheng
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
| | - Jiaqi Tang
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China.,e Institute of Laboratory Medicine ; Jinling Hospital ; Nanjing , China
| | - Changjun Wang
- b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
| | - Youjun Feng
- f Center for Infection & Immunity ; Department of Medical Microbiology & Parasitology ; Zhejiang University School of Medicine ; Hangzhou, Zhejiang , China
| | - Jimin Gao
- a School of Laboratory Medicine and Life Science ; Wenzhou Medical University ; Wenzhou , China
| | - Xiuzhen Pan
- a School of Laboratory Medicine and Life Science ; Wenzhou Medical University ; Wenzhou , China.,b Department of Epidemiology ; Research Institute for Medicine of Nanjing Command ; Nanjing , China
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27
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Perez-Pascual D, Monnet V, Gardan R. Bacterial Cell-Cell Communication in the Host via RRNPP Peptide-Binding Regulators. Front Microbiol 2016; 7:706. [PMID: 27242728 PMCID: PMC4873490 DOI: 10.3389/fmicb.2016.00706] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/28/2016] [Indexed: 12/23/2022] Open
Abstract
Human microbiomes are composed of complex and dense bacterial consortia. In these environments, bacteria are able to react quickly to change by coordinating their gene expression at the population level via small signaling molecules. In Gram-positive bacteria, cell–cell communication is mostly mediated by peptides that are released into the extracellular environment. Cell–cell communication based on these peptides is especially widespread in the group Firmicutes, in which they regulate a wide array of biological processes, including functions related to host–microbe interactions. Among the different agents of communication, the RRNPP family of cytoplasmic transcriptional regulators, together with their cognate re-internalized signaling peptides, represents a group of emerging importance. RRNPP members that have been studied so far are found mainly in species of bacilli, streptococci, and enterococci. These bacteria are characterized as both human commensal and pathogenic, and share different niches in the human body with other microorganisms. The goal of this mini-review is to present the current state of research on the biological relevance of RRNPP mechanisms in the context of the host, highlighting their specific roles in commensalism or virulence.
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Affiliation(s)
- David Perez-Pascual
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas France
| | - Véronique Monnet
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas France
| | - Rozenn Gardan
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas France
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28
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Gao T, Tan M, Liu W, Zhang C, Zhang T, Zheng L, Zhu J, Li L, Zhou R. GidA, a tRNA Modification Enzyme, Contributes to the Growth, and Virulence of Streptococcus suis Serotype 2. Front Cell Infect Microbiol 2016; 6:44. [PMID: 27148493 PMCID: PMC4835480 DOI: 10.3389/fcimb.2016.00044] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 03/27/2016] [Indexed: 11/16/2022] Open
Abstract
Glucose-inhibited division protein (GidA), is a tRNA modification enzyme functioning together with MnmE in the addition of a carboxymethylaminomethyl group to position 5 of the anticodon wobble uridine of tRNA. Here, we report a GidA homolog from a Chinese isolate SC-19 of the zoonotic Streptococcus suis serotype 2 (SS2). gidA disruption led to a defective growth, increased capsule thickness, and reduced hemolytic activity. Moreover, the gidA deletion mutant (ΔgidA) displayed reduced mortality and bacterial loads in mice, reduced ability of adhesion to and invasion in epithelial cells, and increased sensitivity to phagocytosis. The iTRAQ analysis identified 372 differentially expressed (182 up- and 190 down-regulated) proteins in ΔgidA and SC-19. Numerous DNA replication, cell division, and virulence associated proteins were downregulated, whereas many capsule synthesis enzymes were upregulated by gidA disruption. This is consistent with the phenotypes of the mutant. Thus, GidA is a translational regulator that plays an important role in the growth, cell division, capsule biosynthesis, and virulence of SS2. Our findings provide new insight into the regulatory function of GidA in bacterial pathogens.
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Affiliation(s)
- Ting Gao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; Veterinary Medicine Laboratory, Institute of Animal Husbandry and Veterinary Science, Hubei Academy of Agricultural ScienceWuhan, China; Wuhan Chopper Biology Co., Ltd.Wuhan, China
| | - Meifang Tan
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Wanquan Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Chunyan Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Tengfei Zhang
- Veterinary Medicine Laboratory, Institute of Animal Husbandry and Veterinary Science, Hubei Academy of Agricultural Science Wuhan, China
| | - Linlin Zheng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Jiawen Zhu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University Wuhan, China
| | - Lu Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; Cooperative Innovation Center of Sustainable Pig ProductionWuhan, China
| | - Rui Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural UniversityWuhan, China; Cooperative Innovation Center of Sustainable Pig ProductionWuhan, China
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29
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Feng L, Zhu J, Chang H, Gao X, Gao C, Wei X, Yuan F, Bei W. The CodY regulator is essential for virulence in Streptococcus suis serotype 2. Sci Rep 2016; 6:21241. [PMID: 26883762 PMCID: PMC4756307 DOI: 10.1038/srep21241] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 01/20/2016] [Indexed: 01/10/2023] Open
Abstract
The main role of CodY, a global regulatory protein in most low G + C gram-positive bacteria, is in transcriptional repression. To study the functions of CodY in Streptococcus suis serotype 2 (S. suis 2), a mutant codY clone named ∆codY was constructed to explore the phenotypic variation between ∆codY and the wild-type strain. The result showed that the codY mutation significantly inhibited cell growth, adherence and invasion ability of S. suis 2 to HEp-2 cells. The codY mutation led to decreased binding of the pathogen to the host cells, easier clearance by RAW264.7 macrophages and decreased growth ability in fresh blood of Cavia porcellus. The codY mutation also attenuated the virulence of S. suis 2 in BALB/c mice. Morphological analysis revealed that the codY mutation decreased the thickness of the capsule of S. suis 2 and changed the surface structures analylized by SDS-PAGE. Finally, the codY mutation altered the expressions of many virulence related genes, including sialic acid synthesis genes, leading to a decreased sialic acid content in capsule. Overall, mutation of codY modulated bacterial virulence by affecting the growth and colonization of S. suis 2, and at least via regulating sialic acid synthesis and capsule thickness.
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Affiliation(s)
- Liping Feng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Shanghai Laboratory Animal Research Center, Shanghai 201203, China
| | - Jiawen Zhu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Haitao Chang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaoping Gao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Cheng Gao
- Shanghai Laboratory Animal Research Center, Shanghai 201203, China
| | - Xiaofeng Wei
- Shanghai Laboratory Animal Research Center, Shanghai 201203, China
| | - Fangyan Yuan
- Hubei key laboratory of Animal Embryo and Molecular Breeding, Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan 430070, China
| | - Weicheng Bei
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Cooperative Innovation Center of Sustainable Pig Production, Wuhan 430070, China
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Ji X, Sun Y, Liu J, Zhu L, Guo X, Lang X, Feng S. A novel virulence-associated protein, vapE, in Streptococcus suis serotype 2. Mol Med Rep 2016; 13:2871-7. [PMID: 26821177 DOI: 10.3892/mmr.2016.4818] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 12/21/2015] [Indexed: 11/06/2022] Open
Abstract
Streptococcus suis serotype 2 (SS2) is an important pathogen that affects pigs. However, neither its virulence nor its pathogenesis of infection has yet to be fully elucidated. The present study identifies a novel virulence‑associated protein E gene (vapE) of SS2. To investigate the importance of vapE in SS2 infection, a vapE knock‑out mutant based on SS2 wild‑type strain ZY458 was designated 458ΔvapE. 458ΔvapE was generated through homologous recombination, using a combined plasmid with a vapE knock‑out fragment and a pSET4s suicide vector. Additionally, the 458ΔvapE strain was transformed by a pAT18 shuttle plasmid containing the vapE gene. A functionally complemented strain for the vapE gene [termed 458ΔvapE (pvapE)] was constructed. Animal experiments demonstrated that mice infected with ZY458 and 458ΔvapE (pvapE) exhibited severe clinical symptoms, including depression, apathy, fever, anorexia, emaciation, swollen eyes and neural disorders, and died within two days of infection. All mice infected with ZY458, and 85% of mice infected with 458ΔvapE (pvapE), died within 2 days of infection. In contrast, mice inoculated with 458ΔvapE exhibited only mild clinical symptoms in the first 2 days following infection, and recovered within a week. A bacterial colonization assay demonstrated the ability of the 458ΔvapE mutant SS2 strain to colonize the heart, liver, spleen, lung and kidney of infected mice. PCR analysis of the vapE gene revealed that functional vapE was detected in virulent strains, but not in avirulent and carrier strains of S. suis SS2. These findings indicate that vapE is important for the pathogenesis of SS2.
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Affiliation(s)
- Xue Ji
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
| | - Yang Sun
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
| | - Jun Liu
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
| | - Lingwei Zhu
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
| | - Xuejun Guo
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
| | - Xulong Lang
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
| | - Shuzhang Feng
- Molecular Bacteriology Department, Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, Jilin 130122, P.R. China
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Virulence genotyping and population analysis of Streptococcus suis serotype 2 isolates from China. INFECTION GENETICS AND EVOLUTION 2015; 36:483-489. [DOI: 10.1016/j.meegid.2015.08.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 08/16/2015] [Accepted: 08/18/2015] [Indexed: 11/13/2022]
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Hatrongjit R, Kerdsin A, Gottschalk M, Takeuchi D, Hamada S, Oishi K, Akeda Y. First human case report of sepsis due to infection with Streptococcus suis serotype 31 in Thailand. BMC Infect Dis 2015; 15:392. [PMID: 26420029 PMCID: PMC4588491 DOI: 10.1186/s12879-015-1136-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 09/21/2015] [Indexed: 01/11/2023] Open
Abstract
Background Streptococcus suis is a zoonotic pathogen that causes invasive infections in humans and pigs. It has been reported that S. suis infection in humans is mostly caused by serotype 2. However, human cases caused by other serotypes have rarely been reported. This is the first report of a human case of infection with S. suis serotype 31 in Thailand. Case presentation A 55-year-old male alcohol misuser with liver cirrhosis was admitted with sepsis to a hospital in the Central Region of Thailand. He had consumed a homemade, raw pork product prior to the onset of illness. He was alive after treatment with ceftriaxone and no complication occurred. An isolate from blood culture at the hospital was suspected as viridans group Streptococcus. It was confirmed at a reference laboratory as S. suis serotype 31 by biochemical tests, 16S rDNA sequencing, and multiplex polymerase chain reaction for serotyping, but it was untypable by the co-agglutination test with antisera against recognized S. suis serotypes, suggesting loss of capsular material. The absence of a capsule was confirmed by transmission electron microscopy. The isolate was confirmed to be sequence type 221, with 13 putative virulence genes that are usually found in serotype 2 strains. Conclusion We should be aware of the emergence of S. suis infections caused by uncommon serotypes in patients with predisposing conditions. Laboratory capacity to identify S. suis in the hospital is needed in developing countries, which can contribute to enhanced surveillance, epidemiological control, and prevention strategies in the prevalent area. Electronic supplementary material The online version of this article (doi:10.1186/s12879-015-1136-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rujirat Hatrongjit
- Faculty of Science and Engineering, Kasetsart University Chalermphrakiat Sakon Nakhon Province Campus, Muang, Sakon Nakhon Province, 47000, Thailand.
| | - Anusak Kerdsin
- National Institute of Health, Department of Medical Sciences, Ministry of Public Health, Tiwanon Road, Muang, Nonthaburi Province, 11000, Thailand. .,Present address: Faculty of Public Health, Kasetsart University Chalermphrakiat Sakon Nakhon Province Campus, Sakon Nakhon, Thailand.
| | | | - Dan Takeuchi
- Laboratory of Clinical Research on Infectious Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Shigeyuki Hamada
- Thailand-Japan Research Collaboration Center on Emerging and Re-emerging Infections, Nonthaburi Province, Thailand.
| | - Kazunori Oishi
- Infectious Disease Surveillance Center, National Institute of Infectious Diseases, Shinjyuku, Tokyo, Japan.
| | - Yukihiro Akeda
- Laboratory of Clinical Research on Infectious Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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Abstract
Acquisition and metabolism of carbohydrates are essential for host colonization and pathogenesis of bacterial pathogens. Different bacteria can uptake different lines of carbohydrates via ABC transporters, in which ATPase subunits energize the transport though ATP hydrolysis. Some ABC transporters possess their own ATPases, while some share a common ATPase. Here we identified MsmK, an ATPase from Streptococcus suis, an emerging zoonotic bacterium causing dead infections in pigs and humans. Genetic and biochemistry studies revealed that the MsmK was responsible for the utilization of raffinose, melibiose, maltotetraose, glycogen and maltotriose. In infected mice, the msmK-deletion mutant showed significant defects of survival and colonization when compared with its parental and complementary strains. Taken together, MsmK is an ATPase that contributes to multiple carbohydrates utilization and host colonization of S. suis. This study gives new insight into our understanding of the carbohydrates utilization and its relationship to the pathogenesis of this zoonotic pathogen.
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Two Spx regulators modulate stress tolerance and virulence in Streptococcus suis serotype 2. PLoS One 2014; 9:e108197. [PMID: 25264876 PMCID: PMC4180751 DOI: 10.1371/journal.pone.0108197] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 08/18/2014] [Indexed: 01/08/2023] Open
Abstract
Streptococcus suis serotype 2 is an important zoonotic pathogen causing severe infections in pigs and humans. The pathogenesis of S. suis 2 infections, however, is still poorly understood. Spx proteins are a group of global regulators involved in stress tolerance and virulence. In this study, we characterized two orthologs of the Spx regulator, SpxA1 and SpxA2 in S. suis 2. Two mutant strains (ΔspxA1 and ΔspxA2) lacking the spx genes were constructed. The ΔspxA1 and ΔspxA2 mutants displayed different phenotypes. ΔspxA1 exhibited impaired growth in the presence of hydrogen peroxide, while ΔspxA2 exhibited impaired growth in the presence of SDS and NaCl. Both mutants were defective in medium lacking newborn bovine serum. Using a murine infection model, we demonstrated that the abilities of the mutant strains to colonize the tissues were significantly reduced compared to that of the wild-type strain. The mutant strains also showed a decreased level of survival in pig blood. Microarray analysis revealed a global regulatory role for SpxA1 and SpxA2. Furthermore, we demonstrated for the first time that Spx is involved in triggering the host inflammatory response. Collectively, our data suggest that SpxA1 and SpxA2 are global regulators that are implicated in stress tolerance and virulence in S. suis 2.
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Jimenez JC, Federle MJ. Quorum sensing in group A Streptococcus. Front Cell Infect Microbiol 2014; 4:127. [PMID: 25309879 PMCID: PMC4162386 DOI: 10.3389/fcimb.2014.00127] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 08/26/2014] [Indexed: 01/05/2023] Open
Abstract
Quorum sensing (QS) is a widespread phenomenon in the microbial world that has important implications in the coordination of population-wide responses in several bacterial pathogens. In Group A Streptococcus (GAS), many questions surrounding QS systems remain to be solved pertaining to their function and their contribution to the GAS lifestyle in the host. The QS systems of GAS described to date can be categorized into four groups: regulator gene of glucosyltransferase (Rgg), Sil, lantibiotic systems, and LuxS/AI-2. The Rgg family of proteins, a conserved group of transcription factors that modify their activity in response to signaling peptides, has been shown to regulate genes involved in virulence, biofilm formation and competence. The sil locus, whose expression is regulated by the activity of signaling peptides and a putative two-component system (TCS), has been implicated on regulating genes involved with invasive disease in GAS isolates. Lantibiotic regulatory systems are involved in the production of bacteriocins and their autoregulation, and some of these genes have been shown to target both bacterial organisms as well as processes of survival inside the infected host. Finally AI-2 (dihydroxy pentanedione, DPD), synthesized by the LuxS enzyme in several bacteria including GAS, has been proposed to be a universal bacterial communication molecule. In this review we discuss the mechanisms of these four systems, the putative functions of their targets, and pose critical questions for future studies.
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Affiliation(s)
- Juan Cristobal Jimenez
- Department of Microbiology and Immunology, College of Medicine, University of Illinois at Chicago Chicago, IL, USA
| | - Michael J Federle
- Department of Medicinal Chemistry and Pharmacognosy, Center for Pharmaceutical Biotechnology, College of Pharmacy, University of Illinois at Chicago Chicago, IL, USA
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36
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Effect of Tran on virulence through regulating metabolism and stress tolerance of Streptococcus suis serotype 2. Microbiol Res 2014; 169:666-74. [DOI: 10.1016/j.micres.2014.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 03/05/2014] [Accepted: 03/09/2014] [Indexed: 11/19/2022]
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Wu Z, Wu C, Shao J, Zhu Z, Wang W, Zhang W, Tang M, Pei N, Fan H, Li J, Yao H, Gu H, Xu X, Lu C. The Streptococcus suis transcriptional landscape reveals adaptation mechanisms in pig blood and cerebrospinal fluid. RNA (NEW YORK, N.Y.) 2014; 20:882-898. [PMID: 24759092 PMCID: PMC4024642 DOI: 10.1261/rna.041822.113] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Accepted: 03/11/2014] [Indexed: 06/03/2023]
Abstract
Streptococcus suis (SS) is an important pathogen of pigs, and it is also recognized as a zoonotic agent for humans. SS infection may result in septicemia or meningitis in the host. However, little is known about genes that contribute to the virulence process and survival within host blood or cerebrospinal fluid (CSF). Small RNAs (sRNA) have emerged as key regulators of virulence in several bacteria, but they have not been investigated in SS. Here, using a differential RNA-sequencing approach and RNAs from SS strain P1/7 grown in rich medium, pig blood, or CSF, we present the SS genome-wide map of 793 transcriptional start sites and 370 operons. In addition to identifying 29 sRNAs, we show that five sRNA deletion mutants attenuate SS virulence in a zebrafish infection model. Homology searches revealed that 10 sRNAs were predicted to be present in other pathogenic Streptococcus species. Compared with wild-type strain P1/7, sRNAs rss03, rss05, and rss06 deletion mutants were significantly more sensitive to killing by pig blood. It is possible that rss06 contributes to SS virulence by indirectly activating expression of SSU0308, a virulence gene encoding a zinc-binding lipoprotein. In blood, genes involved in the synthesis of capsular polysaccharide (CPS) and subversion of host defenses were up-regulated. In contrast, in CSF, genes for CPS synthesis were down-regulated. Our study is the first analysis of SS sRNAs involved in virulence and has both improved our understanding of SS pathogenesis and increased the number of sRNAs known to play definitive roles in bacterial virulence.
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Affiliation(s)
- Zongfu Wu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
| | | | - Jing Shao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
| | | | - Weixue Wang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
| | | | - Min Tang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
| | - Na Pei
- BGI-Shenzhen, Shenzhen 518083, China
| | - Hongjie Fan
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | | | - Huochun Yao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
| | - Hongwei Gu
- Jiangsu Engineering Research Center for microRNA Biology and Biotechnology, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, China
| | - Xun Xu
- BGI-Shenzhen, Shenzhen 518083, China
| | - Chengping Lu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China
- OIE Reference Laboratory for Swine Streptococcosis, Nanjing 210095, China
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Tang Y, Zhang X, Yin Y, Hardwidge PR, Fang W. Streptococcus suis type 2 SSU0587 protein is a beta-galactosidase that contributes to bacterial adhesion but not to virulence in mice. J Vet Med Sci 2014; 76:1055-9. [PMID: 24670993 PMCID: PMC4143649 DOI: 10.1292/jvms.13-0625] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Bacterial surface proteins play key roles in virulence and often contribute to bacterial adhesion and invasion. We discovered that the Streptococcus suis type 2 (SS2) gene SSU0587 encodes a protein of 1,491 amino acids that possesses β-galactosidase activity. The surface association of the protein was dependent upon sortase activity. Deleting SSU0587 from clinical SS2 isolate JX081101 caused a loss of both β-galactosidase activity and adherence to microvascular endothelial cells. Deleting SSU0587 had no measurable impact on either invasion of microvascular endothelial cells or on virulence in a murine infection model, although the concentration of JX081101ΔSSU0587 was reduced in the brains of infected mice, as compared with the pathogen loads of the wild-type strain.
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Affiliation(s)
- Yulong Tang
- Institute of Subtropical Agriculture, Chinese Academy of Sciences, Research Center of Healthy Breeding Livestock & Poultry, Hunan Engineering & Research Center of Animal & Poultry Science, Key Lab Agro-ecology Processing Subtropical Region, Scientific Observational and Experimental Station of Animal Nutrition and Feed Science in South-Central China, Ministry of Agriculture, Changsha, Hunan, People's Republic of China
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Feng Y, Zhang H, Wu Z, Wang S, Cao M, Hu D, Wang C. Streptococcus suis infection: an emerging/reemerging challenge of bacterial infectious diseases? Virulence 2014; 5:477-97. [PMID: 24667807 PMCID: PMC4063810 DOI: 10.4161/viru.28595] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Streptococcus suis (S. suis) is a family of pathogenic gram-positive bacterial strains that represents a primary health problem in the swine industry worldwide. S. suis is also an emerging zoonotic pathogen that causes severe human infections clinically featuring with varied diseases/syndromes (such as meningitis, septicemia, and arthritis). Over the past few decades, continued efforts have made significant progress toward better understanding this zoonotic infectious entity, contributing in part to the elucidation of the molecular mechanism underlying its high pathogenicity. This review is aimed at presenting an updated overview of this pathogen from the perspective of molecular epidemiology, clinical diagnosis and typing, virulence mechanism, and protective antigens contributing to its zoonosis.
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Affiliation(s)
- Youjun Feng
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases & State Key Laboratory for Diagnosis and Treatment of Infectious Disease; First Affiliated Hospital; Zhejiang University School of Medicine; Hangzhou, Zhejiang, PR China; Department of Medical Microbiology and Parasitology; Zhejiang University School of Medicine; Hangzhou, Zhejiang, PR China
| | - Huimin Zhang
- University of Illinois at Urbana-Champaign (UIUC); Urbana, IL USA
| | - Zuowei Wu
- Department of Veterinary Microbiology and Preventive Medicine; Iowa State University; Ames, IA USA
| | - Shihua Wang
- College of Life Sciences; Fujian Agriculture and Forestry University; Fuzhou, Fujian, PR China
| | - Min Cao
- Department of Epidemiology; Research Institute for Medicine of Nanjing Command; Nanjing, Jiangsu, PR China
| | - Dan Hu
- Department of Epidemiology; Research Institute for Medicine of Nanjing Command; Nanjing, Jiangsu, PR China
| | - Changjun Wang
- Department of Epidemiology; Research Institute for Medicine of Nanjing Command; Nanjing, Jiangsu, PR China
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The β-galactosidase (BgaC) of the zoonotic pathogen Streptococcus suis is a surface protein without the involvement of bacterial virulence. Sci Rep 2014; 4:4140. [PMID: 24556915 PMCID: PMC3931136 DOI: 10.1038/srep04140] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/30/2014] [Indexed: 12/27/2022] Open
Abstract
Streptococcal pathogens have evolved to express exoglycosidases, one of which is BgaC β-galactosidase, to deglycosidate host surface glycolconjucates with exposure of the polysaccharide receptor for bacterial adherence. The paradigm BgaC protein is the bgaC product of Streptococcus, a bacterial surface-exposed β-galactosidase. Here we report the functional definition of the BgaC homologue from an epidemic Chinese strain 05ZYH33 of the zoonotic pathogen Streptococcus suis. Bioinformatics analyses revealed that S. suis BgaC shared the conserved active sites (W240, W243 and Y454). The recombinant BgaC protein of S. suis was purified to homogeneity. Enzymatic assays confirmed its activity of β-galactosidase. Also, the hydrolysis activity was found to be region-specific and sugar-specific for the Gal β-1,3-GlcNAc moiety of oligosaccharides. Flow cytometry analyses combined with immune electron microscopy demonstrated that S. suis BgaC is an atypical surface-anchored protein in that it lacks the “LPXTG” motif for typical surface proteins. Integrative evidence from cell lines and mice-based experiments showed that an inactivation of bgaC does not significantly impair the ability of neither adherence nor anti-phagocytosis, and consequently failed to attenuate bacterial virulence, which is somewhat similar to the scenario seen with S. pneumoniae. Therefore we concluded that S. suis BgaC is an atypical surface-exposed protein without the involvement of bacterial virulence.
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Zhang S, Min X, Guo Z, Zhang H, Huang A, Yin Y, Wang D. Cloning, purification, crystallization and preliminary X-ray studies of the putative transcriptional regulator SPD0280 from Streptococcus pneumoniae D39. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:1246-8. [PMID: 24192360 DOI: 10.1107/s1744309113026018] [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: 07/14/2013] [Accepted: 09/20/2013] [Indexed: 11/10/2022]
Abstract
Streptococcus pneumoniae SPD0280 is a hypothetical protein that has been putatively identified as a transcriptional regulator. However, it has very low sequence identity to other well characterized transcriptional regulators. Determination of the three-dimensional structure may provide information for the characterization of proteins; therefore, it was decided to use X-ray diffraction analysis to learn more about this protein. Here, the expression, purification, crystallization and preliminary crystallographic analysis of SPD0280 from S. pneumoniae are reported. The crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 45.886, b = 66.785, c = 150.050 Å, and diffracted to a resolution of 2.5 Å. The crystals are likely to contain one molecule in the asymmetric unit, with a VM value of 2.06 Å(3) Da(-1).
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Affiliation(s)
- Shaocheng Zhang
- Key Laboratory of Molecular Biology on Infectious Disease, Chongqing Medical University, YiXueYuanlu-1, Chongqing 400016, People's Republic of China
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Zheng JX, Li Y, Zhang H, Fan HJ, Lu CP. Identification and characterization of a novel hemolysis-related gene in Streptococcus suis serotype 2. PLoS One 2013; 8:e74674. [PMID: 24069329 PMCID: PMC3775796 DOI: 10.1371/journal.pone.0074674] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 08/02/2013] [Indexed: 11/18/2022] Open
Abstract
Streptococcussuis serotype 2 (SS 2) is an important zoonotic pathogen that has caused two major infectious outbreaks of streptococcal toxic shock syndrome (STSS) in China. A novel gene located in the 89K pathogenicity island (PAI) encoding a putative hemolysin-III-related protein (Hhly3) has been previously characterized. In this study, the SS2 deletion mutant of the exogenous gene hhly3 was constructed by homologous recombination. This protein was found to exhibit cytolytic activity, and hemolytic activity of the hhly3 gene knockout mutant (Δhhly3) was significantly lower than that in the wild-type strain ZY05719. In addition, qRT-PCR revealed that Hhly3 played an important role in the expression of the secreted hemolysin SLY, which may be the key reason for the decreased hemolytic activity. Consequently, compared with the WT strain, the infection and pathogenicity of Δhhly3 was also decreased, as evidenced by in vitro bacterial growth in whole blood and by the in vivo zebrafish test, suggesting that hhly3 is a novel exogenous hemolysis-related gene in SS2 strains.
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Affiliation(s)
- Jun-xi Zheng
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Yue Li
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Hui Zhang
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Hong-jie Fan
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
- Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- * E-mail:
| | - Cheng-ping Lu
- Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
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Kouki A, Pieters RJ, Nilsson UJ, Loimaranta V, Finne J, Haataja S. Bacterial Adhesion of Streptococcus suis to Host Cells and Its Inhibition by Carbohydrate Ligands. BIOLOGY 2013; 2:918-35. [PMID: 24833053 PMCID: PMC3960878 DOI: 10.3390/biology2030918] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 05/22/2013] [Accepted: 05/22/2013] [Indexed: 11/16/2022]
Abstract
Streptococcus suis is a Gram-positive bacterium, which causes sepsis and meningitis in pigs and humans. This review examines the role of known S. suis virulence factors in adhesion and S. suis carbohydrate-based adhesion mechanisms, as well as the inhibition of S. suis adhesion by anti-adhesion compounds in in vitro assays. Carbohydrate-binding specificities of S. suis have been identified, and these studies have shown that many strains recognize Galα1-4Gal-containing oligosaccharides present in host glycolipids. In the era of increasing antibiotic resistance, new means to treat infections are needed. Since microbial adhesion to carbohydrates is important to establish disease, compounds blocking adhesion could be an alternative to antibiotics. The use of oligosaccharides as drugs is generally hampered by their relatively low affinity (micromolar) to compete with multivalent binding to host receptors. However, screening of a library of chemically modified Galα1-4Gal derivatives has identified compounds that inhibit S. suis adhesion in nanomolar range. Also, design of multivalent Galα1-4Gal-containing dendrimers has resulted in a significant increase of the inhibitory potency of the disaccharide. The S. suis adhesin binding to Galα1-4Gal-oligosaccharides, Streptococcal adhesin P (SadP), was recently identified. It has a Galα1-4Gal-binding N-terminal domain and a C-terminal LPNTG-motif for cell wall anchoring. The carbohydrate-binding domain has no homology to E. coli P fimbrial adhesin, which suggests that these Gram-positive and Gram-negative bacterial adhesins recognizing the same receptor have evolved by convergent evolution. SadP adhesin may represent a promising target for the design of anti-adhesion ligands for the prevention and treatment of S. suis infections.
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Affiliation(s)
- Annika Kouki
- Department of Medical Biochemistry and Genetics, University of Turku, Kiinamyllynkatu 10, Turku FI-20520, Finland.
| | - Roland J Pieters
- Department of Medicinal Chemistry and Chemical Biology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, P.O. Box 80082, Utrecht 3508 TB, The Netherlands.
| | - Ulf J Nilsson
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, POB 124, Lund SE-22100, Sweden.
| | - Vuokko Loimaranta
- Department of Medical Biochemistry and Genetics, University of Turku, Kiinamyllynkatu 10, Turku FI-20520, Finland.
| | - Jukka Finne
- Department of Biosciences, Division of Biochemistry and Biotechnology, University of Helsinki, P.O.B. 56, Helsinki FI-00014, Finland.
| | - Sauli Haataja
- Department of Medical Biochemistry and Genetics, University of Turku, Kiinamyllynkatu 10, Turku FI-20520, Finland.
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Zouhir S, Perchat S, Nicaise M, Perez J, Guimaraes B, Lereclus D, Nessler S. Peptide-binding dependent conformational changes regulate the transcriptional activity of the quorum-sensor NprR. Nucleic Acids Res 2013; 41:7920-33. [PMID: 23793817 PMCID: PMC3763537 DOI: 10.1093/nar/gkt546] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The transcriptional regulator NprR controls the expression of genes essential for the adaptative response of Bacillus cereus. NprR belongs to the RNPP family of directly regulated quorum sensors from Gram-positive bacteria. It is activated by the re-imported signaling peptide NprX. To elucidate the activation mechanism of this quorum-sensing system, we analyzed the conformation changes induced on binding of NprX. We solved the crystal structure of the NprR/NprX binary complex and characterized the apo form of NprR in solution. We demonstrated that apo NprR is a dimer that switches to a tetramer in the presence of NprX. Mutagenesis, and functional analysis allowed us to identify the protein and peptide residues directly involved in the NprR activation process. Based on the comparison with the Rap proteins, we propose a model for the peptide-induced conformational change allowing the apo dimer to switch to an active tetramer specifically recognizing target DNA sequences.
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Affiliation(s)
- Samira Zouhir
- CNRS, UPR3082, Laboratoire d'Enzymologie et Biochimie Structurales, Gif sur Yvette 91198, France, INRA, UMR1319 Micalis, La Minière, Guyancourt 78280, France, AgroParisTech, UMR1319 Micalis, Jouy-en-Josas 78350, France, Université Paris-Sud, UMR8619, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Orsay 91405, France and Synchrotron SOLEIL, 91192 Gif sur Yvette, France
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Enterococcal Rgg-like regulator ElrR activates expression of the elrA operon. J Bacteriol 2013; 195:3073-83. [PMID: 23645602 DOI: 10.1128/jb.00121-13] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The Enterococcus faecalis leucine-rich protein ElrA promotes virulence by stimulating bacterial persistence in macrophages and production of the interleukin-6 (IL-6) cytokine. The ElrA protein is encoded within an operon that is poorly expressed under laboratory conditions but induced in vivo. In this study, we identify ef2687 (renamed elrR), which encodes a member of the Rgg (regulator gene for glucosyltransferase) family of putative regulatory proteins. Using quantitative reverse transcription-PCR, translational lacZ fusions, and electrophoretic mobility shift assays, we demonstrate that ElrR positively regulates expression of elrA. These results correlate with the attenuated virulence of the ΔelrR strain in a mouse peritonitis model. Virulence of simple and double elrR and elrA deletion mutants also suggests a remaining ElrR-independent expression of elrA in vivo and additional virulence-related genes controlled by ElrR.
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Francius G, Henry R, Duval JFL, Bruneau E, Merlin J, Fahs A, Leblond-Bourget N. Thermo-regulated adhesion of the Streptococcus thermophilus Δrgg0182 strain. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:4847-4856. [PMID: 23530723 DOI: 10.1021/la4001895] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The physicochemical determinants governing the temperature-dependent adhesion of Streptococcus thermophilus to abiotic surfaces are identified under physiological condition for cells either lacking or not the Rgg0182 transcriptional regulator involved in their thermal adaptation. For that purpose, the wild type LMG18311 strain and Δrgg0182 mutant were imaged using highly resolved atomic force microscopy (AFM) at various cell growth temperatures (42 to 55 °C). The corresponding hydrophobic/hydrophilic balance of the cells was quantitatively addressed via the measurement by chemical force microcopy of their adhesion to a reference hydrophobic surface. Analysis of force-separation distance curves further allowed us to discriminate cell surfaces according to the presence or absence of biopolymers. These results were interpreted in relation to the measured adhesion of the Δrgg0182 mutant onto the hydrophobic wall of microwells in the temperature range from 46 to 52 °C. It is evidenced that the viscoelastic Δrgg0182 cell envelop behaves as a thermo-responsive film whose hydrophobicity increases with increasing temperature, thereby favoring cell attachment to hydrophobic surfaces. Regardless cell growth temperature, wild-type cells do not attach to hydrophobic surfaces and the presence of the Rgg0182 transcriptional regulator is associated with the synthesis of hydrophilic cell surface biopolymers. Throughout, the impact of electrostatics on bioadhesion is ruled out upon examination of electrohydrodynamic cell properties at 50 °C.
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Affiliation(s)
- Grégory Francius
- Université de Lorraine, Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, LCPME, UMR 7564, Villers-lès-Nancy F-54600, France.
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Abstract
UNLABELLED Recent studies have established the fact that multiple members of the Rgg family of transcriptional regulators serve as key components of quorum sensing (QS) pathways that utilize peptides as intercellular signaling molecules. We previously described a novel QS system in Streptococcus pyogenes which utilizes two Rgg-family regulators (Rgg2 and Rgg3) that respond to neighboring signaling peptides (SHP2 and SHP3) to control gene expression and biofilm formation. We have shown that Rgg2 is a transcriptional activator of target genes, whereas Rgg3 represses expression of these genes, and that SHPs function to activate the QS system. The mechanisms by which Rgg proteins regulate both QS-dependent and QS-independent processes remain poorly defined; thus, we sought to further elucidate how Rgg2 and Rgg3 mediate gene regulation. Here we provide evidence that S. pyogenes employs a unique mechanism of direct competition between the antagonistic, peptide-responsive proteins Rgg2 and Rgg3 for binding at target promoters. The highly conserved, shared binding sites for Rgg2 and Rgg3 are located proximal to the -35 nucleotide in the target promoters, and the direct competition between the two regulators results in concentration-dependent, exclusive occupation of the target promoters that can be skewed in favor of Rgg2 in vitro by the presence of SHP. These results suggest that exclusionary binding of target promoters by Rgg3 may prevent Rgg2 binding under SHP-limiting conditions, thereby preventing premature induction of the quorum sensing circuit. IMPORTANCE Rgg-family transcriptional regulators are widespread among low-G+C Gram-positive bacteria and in many cases contribute to bacterial physiology and virulence. Only recently was it discovered that several Rgg proteins function in cell-to-cell communication (quorum sensing [QS]) via direct interaction with signaling peptides. The mechanism(s) by which Rgg proteins mediate regulation is poorly understood, and further insight into Rgg function is anticipated to be of great importance for the understanding of both regulatory-network architecture and intercellular communication in Rgg-containing species. The results of this study on the Rgg2/3 QS circuit of S. pyogenes demonstrate that DNA binding of target promoters by the activator Rgg2 is directly inhibited by competitive binding by the repressor Rgg3, thereby preventing transcriptional activation of the target genes and premature induction of the QS circuit. This is a unique regulatory mechanism among Rgg proteins and other peptide-responsive QS regulators.
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Structural basis for the activation mechanism of the PlcR virulence regulator by the quorum-sensing signal peptide PapR. Proc Natl Acad Sci U S A 2012; 110:1047-52. [PMID: 23277548 DOI: 10.1073/pnas.1213770110] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The quorum-sensing regulator PlcR is the master regulator of most known virulence factors in Bacillus cereus. It is a helix-turn-helix (HTH)-type transcription factor activated upon binding of its cognate signaling peptide PapR on a tetratricopeptide repeat-type regulatory domain. The structural and functional properties of PlcR have defined a new family of sensor regulators, called the RNPP family (for Rap, NprR, PrgX, and PlcR), in Gram-positive bacteria. To fully understand the activation mechanism of PlcR, we took a closer look at the conformation changes induced upon binding of PapR and of its target DNA, known as PlcR-box. For that purpose we have determined the structures of the apoform of PlcR (Apo PlcR) and of the ternary complex of PlcR with PapR and the PlcR-box from the plcA promoter. Comparison of the apoform of PlcR with the previously published structure of the PlcR-PapR binary complex shows how a small conformational change induced in the C-terminal region of the tetratricopeptide repeat (TPR) domain upon peptide binding propagates via the linker helix to the N-terminal HTH DNA-binding domain. Further comparison with the PlcR-PapR-DNA ternary complex shows how the activation of the PlcR dimer allows the linker helix to undergo a drastic conformational change and subsequent proper positioning of the HTH domains in the major groove of the two half sites of the pseudopalindromic PlcR-box. Together with random mutagenesis experiments and interaction measurements using peptides from distinct pherogroups, this structural analysis allows us to propose a molecular mechanism for this functional switch.
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Tang Y, Wu W, Zhang X, Lu Z, Chen J, Fang W. Catabolite control protein A of Streptococcus suis type 2 contributes to sugar metabolism and virulence. J Microbiol 2012; 50:994-1002. [PMID: 23274986 DOI: 10.1007/s12275-012-2035-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 08/21/2012] [Indexed: 10/27/2022]
Abstract
Catabolite control protein A (CcpA) is the major transcriptional regulator in carbon catabolite repression in several Gram-positive bacteria. We attempted to characterize the role of a CcpA homologue of Streptococcus suis type 2 in sugar metabolism and virulence. Addition of glucose or sucrose to the defined medium significantly reduced the activity of raffinose-inducible α-galactosidase, cellobiose-inducible β-glucosidase, and maltose-inducible α-glucosidase of the wild-type strain by about 9, 4, and 2-3 fold, respectively. Deletion of ccpA substantially derepressed the effects of repressing sugars on α-galactosidase or β-glucosidase activity. The ccpA deletion mutant showed reduced expression of virulence genes sly and eno (P<0.05), decreased adhesion to and invasion into endothelial cells (P<0.05), and attenuated virulence to mice with significant reduction of death rate and bacterial burden in organs, as compared to the wild-type strain. Both the in vitro and in vivo defect phenotypes were reversible by ccpA complementation. Thus, this study shows that CcpA of S. suis type 2 plays an important role in carbon catabolite repression and virulence.
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Affiliation(s)
- Yulong Tang
- Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, PR China
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Inactivation of the sodA gene of Streptococcus suis type 2 encoding superoxide dismutase leads to reduced virulence to mice. Vet Microbiol 2012; 158:360-6. [DOI: 10.1016/j.vetmic.2012.02.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Revised: 02/19/2012] [Accepted: 02/20/2012] [Indexed: 12/23/2022]
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