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Shan X, Fu J, Li X, Peng X, Chen L. Comparative proteomics and secretomics revealed virulence, and coresistance-related factors in non O1/O139 Vibrio cholerae recovered from 16 species of consumable aquatic animals. J Proteomics 2022; 251:104408. [PMID: 34737110 DOI: 10.1016/j.jprot.2021.104408] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/12/2021] [Accepted: 10/13/2021] [Indexed: 02/06/2023]
Abstract
Vibrio cholerae can cause pandemic cholera in humans. The bacterium resides in aquatic environments worldwide. Identification of risk factors of V. cholerae in aquatic products is imperative for assuming food safety. In this study, we determined virulence-associated genes, cross-resistance between antibiotics and heavy metals, and genome fingerprinting profiles of non O1/O139 V. cholerae isolates (n = 20) recovered from 16 species of consumable aquatic animals. Secretomes and proteomes of V. cholerae with distinct genotypes and phenotypes were obtained by using two-dimensional gel electrophoresis (2D-GE) and/or liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques. Comparative secretomic analysis revealed 4 common and 45 differential extracellular proteins among 20 V. cholerae strains, including 13 virulence- and 8 resistance-associated proteins. A total of 21,972 intracellular proteins were identified, and comparative proteomic analysis revealed 215 common and 913 differential intracellular proteins, including 22 virulence- and 8 resistance-associated proteins. Additionally, different secretomes and proteomes were observed between V. cholerae isolates of fish and shellfish origins. A number of novel proteins with unknown function and strain-specific proteins were also discovered in the V. cholerae isolates. SIGNIFICANCE: V. cholerae can cause pandemic cholera in humans. The bacterium is distributed in aquatic environments worldwide. Identification of risk factors of V. cholerae in aquatic products is imperative for assuming food safety. Non-O1/O139 V. cholerae has been reported to cause sporadic cholera-like diarrhea and bacteremia diseases, which indicates virulence factors rather than the major cholera toxin (CT) exist. This study for the first time investigated proteomes and secretomes of non-O1/O139 V. cholerae originating from aquatic animals. This resulted in the identification of a number of virulence and coresistance-related factors, as well as novel proteins and strain-specific proteins in V. cholerae isolates recovered from 16 species of consumable aquatic animals. These results fill gaps for better understanding of pathogenesis and resistance of V. cholerae, and also support the increasing need for novel diagnosis and vaccine targets against the leading waterborne pathogen worldwide.
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Affiliation(s)
- Xinying Shan
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), China Ministry of Agriculture, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Junfeng Fu
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), China Ministry of Agriculture, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Xiaohui Li
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), China Ministry of Agriculture, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Xu Peng
- Archaea Centre, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Lanming Chen
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), China Ministry of Agriculture, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China.
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Molecular mechanisms of inhibiting glucosyltransferases for biofilm formation in Streptococcus mutans. Int J Oral Sci 2021; 13:30. [PMID: 34588414 PMCID: PMC8481554 DOI: 10.1038/s41368-021-00137-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 06/29/2021] [Accepted: 09/02/2021] [Indexed: 02/05/2023] Open
Abstract
Glucosyltransferases (Gtfs) play critical roles in the etiology and pathogenesis of Streptococcus mutans (S. mutans)- mediated dental caries including early childhood caries. Gtfs enhance the biofilm formation and promotes colonization of cariogenic bacteria by generating biofilm extracellular polysaccharides (EPSs), the key virulence property in the cariogenic process. Therefore, Gtfs have become an appealing target for effective therapeutic interventions that inhibit cariogenic biofilms. Importantly, targeting Gtfs selectively impairs the S. mutans virulence without affecting S. mutans existence or the existence of other species in the oral cavity. Over the past decade, numerous Gtfs inhibitory molecules have been identified, mainly including natural and synthetic compounds and their derivatives, antibodies, and metal ions. These therapeutic agents exert their inhibitory role in inhibiting the expression gtf genes and the activities and secretion of Gtfs enzymes with a wide range of sensitivity and effectiveness. Understanding molecular mechanisms of inhibiting Gtfs will contribute to instructing drug combination strategies, which is more effective for inhibiting Gtfs than one drug or class of drugs. This review highlights our current understanding of Gtfs activities and their potential utility, and discusses challenges and opportunities for future exploration of Gtfs as a therapeutic target.
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Atalay HT, Dogruman-Al F, Sarzhanov F, Özmen MC, Tefon AB, Arıbaş YK, Bilgihan K. Effect of Riboflavin/Rose Bengal-Mediated PACK-CXL on Acanthamoeba Trophozoites and Cysts in Vitro. Curr Eye Res 2018; 43:1322-1325. [PMID: 30021467 DOI: 10.1080/02713683.2018.1501074] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PURPOSE To evaluate the antiamoebic properties of photo-activated chromophore for keratitis (PACK)-corneal cross-linking (CXL) (PACK-CXL), in combination with riboflavin (0.1 and 0.25%) or rose bengal (0.1 and 0.2%), for treatment of Acanthamoeba trophozoites and cysts. MATERIALS AND METHODS Cultures of Acanthamoeba castellanii were grown in a fluid medium at a concentration of 2.7 × 105 cell/ml. PACK-CXL was used on A. castellani cells in combination with either riboflavin (0.1 and 0.25%) or rose bengal (0.1 and 0.2%). Riboflavin-containing wells were irradiated with ultraviolet-A (UVA) light (365-nm wavelength). Rose bengal-containing wells were irradiated with green light (523-nm wavelength). A power density of 9 mW/cm2 for 10 min and total irradiation dose of 5.4 J/cm2 was used for both riboflavin and rose bengal. After UVA and green light irradiation, cell viabilities were evaluated, and percentage of dead cells calculated. RESULTS No significant amoebicidal activity was observed following PACK-CXL/riboflavin at either concentration. PACK-CXL/rose bengal, however, was observed to be highly effective in eradicating Acanthamoeba cells at either concentration, with no significant difference observed between the two concentrations. The percentage of dead cells was 63% following treatment at either rose bengal concentration. CONCLUSION PACK-CXL with rose bengal demonstrated pronounced antiamoebic activity against A.castellanii. Further in vitro and in vivo studies are needed to confirm this finding.
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Affiliation(s)
- Hatice Tuba Atalay
- a Department of Ophthalmology, School of Medicine , Gazi University , Ankara , Turkey
| | - Funda Dogruman-Al
- b Department of Medical Microbiology, School of Medicine , Gazi university , Ankara , Turkey
| | - Fakhriddin Sarzhanov
- b Department of Medical Microbiology, School of Medicine , Gazi university , Ankara , Turkey.,c School of Medicine , Ahmet Yesevi International Kazakh-Turkish University , Turkestan , Kazakhstan
| | - Mehmet Cüneyt Özmen
- a Department of Ophthalmology, School of Medicine , Gazi University , Ankara , Turkey
| | - Atike Burçin Tefon
- a Department of Ophthalmology, School of Medicine , Gazi University , Ankara , Turkey
| | - Yavuz Kemal Arıbaş
- a Department of Ophthalmology, School of Medicine , Gazi University , Ankara , Turkey
| | - Kamil Bilgihan
- a Department of Ophthalmology, School of Medicine , Gazi University , Ankara , Turkey
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Dantas GC, Martins PMM, Martins DAB, Gomes E, Ferreira H. A protein expression system for tandem affinity purification in Xanthomonas citri subsp. citri. Braz J Microbiol 2016; 47:518-26. [PMID: 26991273 PMCID: PMC4874617 DOI: 10.1016/j.bjm.2016.01.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 10/23/2015] [Indexed: 11/30/2022] Open
Abstract
Citrus canker, caused by the Gram-negative bacterium Xanthomonas citri subsp. citri (Xac), is one of the most devastating diseases to affect citrus crops. There is no treatment for citrus canker; effective control against the spread of Xac is usually achieved by the elimination of affected plants along with that of asymptomatic neighbors. An in depth understanding of the pathogen is the keystone for understanding of the disease; to this effect we are committed to the development of strategies to ease the study of Xac. Genome sequencing and annotation of Xac revealed that ∼37% of the genome is composed of hypothetical ORFs. To start a systematic characterization of novel factors encoded by Xac, we constructed integrative-vectors for protein expression specific to this bacterium. The vectors allow for the production of TAP-tagged proteins in Xac under the regulation of the xylose promoter. In this study, we show that a TAP-expression vector, integrated into the amy locus of Xac, does not compromise its virulence. Furthermore, our results also demonstrate that the polypeptide TAP can be overproduced in Xac and purified from the soluble phase of cell extracts. Our results substantiate the use of our vectors for protein expression in Xac thus contributing a novel tool for the characterization of proteins and protein complexes generated by this bacterium in vivo.
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Affiliation(s)
- Giordanni C Dantas
- Depto. de Bioquimica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, SP, Brazil
| | - Paula M M Martins
- Depto. de Bioquimica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, SP, Brazil
| | - Daniela A B Martins
- Depto. de Bioquímica e Tecnologia Química, Instituto de Química, Universidade Estadual Paulista, Araraquara, SP, Brazil
| | - Eleni Gomes
- Depto. de Biologia, Universidade Estadual Paulista, São Jose do Rio Preto, SP, Brazil
| | - Henrique Ferreira
- Depto. de Bioquimica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, SP, Brazil.
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Snoussi S, El May A, Coquet L, Chan P, Jouenne T, Dé E, Landoulsi A. Unraveling the effects of static magnetic field stress on cytosolic proteins of Salmonella by using a proteomic approach. Can J Microbiol 2015; 62:338-48. [PMID: 26928316 DOI: 10.1139/cjm-2015-0532] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study investigated the adaptation of Salmonella enterica subsp. enterica serovar Hadar to static magnetic field (SMF) exposure (200 mT, 9 h). The proteomic analysis provides an overview of potentially important cytosolic proteins that Salmonella needs to regulate to survive and adapt to magnetic stress. Via 2-dimensional electrophoresis and liquid chromatography tandem mass spectrometry, we compared cytosolic proteomes before and after exposure to magnetic field. A total of 35 proteins displaying more than a 2-fold change were differentially expressed in exposed cells, among which 25 were upregulated and 10 were downregulated. These proteins can be classified mainly into 6 categories: (i) proteins involved in metabolic pathways of carbohydrates, (ii) chaperones and proteins produced in response to oxidative stress, (iii) proteins involved in energy homeostasis, (iv) elongation factors (EF-Tu and EF-Ts), (v) proteins involved in motility, and (vi) proteins involved in molecules transport. Many of the presented observations could be explained, while some represent still-unknown mechanisms. In addition, this study reveals 5 hypothetical proteins. It seems that the stress response to SMF (200 mT) is essentially set up to avoid oxidative damages, with the overexpression of proteins directly involved in oxidative stress response and metabolic switches to counteract oxidative stress. Interestingly, several proteins induced under SMF exposure are found to overlap with those induced by other stresses, such as heat shock and starvation.
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Affiliation(s)
- Sarra Snoussi
- a Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Bizerte, Tunisie.,b UMR 6270 CNRS, Faculté des sciences, Université de Rouen, 76821 Mont Saint Aignan Cedex, France
| | - Alya El May
- a Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Bizerte, Tunisie
| | - Laurent Coquet
- b UMR 6270 CNRS, Faculté des sciences, Université de Rouen, 76821 Mont Saint Aignan Cedex, France
| | - Philippe Chan
- b UMR 6270 CNRS, Faculté des sciences, Université de Rouen, 76821 Mont Saint Aignan Cedex, France
| | - Thierry Jouenne
- b UMR 6270 CNRS, Faculté des sciences, Université de Rouen, 76821 Mont Saint Aignan Cedex, France
| | - Emmanuelle Dé
- b UMR 6270 CNRS, Faculté des sciences, Université de Rouen, 76821 Mont Saint Aignan Cedex, France
| | - Ahmed Landoulsi
- a Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences de Bizerte, Université de Carthage, 7021 Zarzouna, Bizerte, Tunisie
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Zhao J, Chen M, Quan CS, Fan SD. Mechanisms of quorum sensing and strategies for quorum sensing disruption in aquaculture pathogens. JOURNAL OF FISH DISEASES 2015; 38:771-786. [PMID: 25219871 DOI: 10.1111/jfd.12299] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 06/03/2023]
Abstract
In many countries, infectious diseases are a considerable threat to aquaculture. The pathogenicity of micro-organisms that infect aquaculture systems is closely related to the release of virulence factors and the formation of biofilms, both of which are regulated by quorum sensing (QS). Thus, QS disruption is a potential strategy for preventing disease in aquaculture systems. QS inhibitors (QSIs) not only inhibit the expression of virulence-associated genes but also attenuate the virulence of aquaculture pathogens. In this review, we discuss QS systems in important aquaculture pathogens and focus on the relationship between QS mechanisms and bacterial virulence in aquaculture. We further elucidate QS disruption strategies for targeting aquaculture pathogens. Four main types of QSIs that target aquaculture pathogens are discussed based on their mechanisms of action.
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Affiliation(s)
- J Zhao
- Key Laboratory of Biochemical Engineering State Ethnic Affairs Commission-Ministry of Education, Dalian Nationalities University, Dalian, China
- College of Life Science, Dalian Nationalities University, Dalian, China
| | - M Chen
- College of Bioengineering, Dalian Polytechnic University, Dalian, China
| | - C S Quan
- Key Laboratory of Biochemical Engineering State Ethnic Affairs Commission-Ministry of Education, Dalian Nationalities University, Dalian, China
- College of Life Science, Dalian Nationalities University, Dalian, China
| | - S D Fan
- Key Laboratory of Biochemical Engineering State Ethnic Affairs Commission-Ministry of Education, Dalian Nationalities University, Dalian, China
- College of Life Science, Dalian Nationalities University, Dalian, China
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Lowery CA, Matamouros S, Niessen S, Zhu J, Scolnick J, Lively JM, Cravatt BF, Miller SI, Kaufmann GF, Janda KD. A chemical biology approach to interrogate quorum-sensing regulated behaviors at the molecular and cellular level. ACTA ACUST UNITED AC 2014; 20:903-11. [PMID: 23890008 DOI: 10.1016/j.chembiol.2013.05.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 05/08/2013] [Accepted: 05/29/2013] [Indexed: 10/26/2022]
Abstract
Small molecule probes have been used extensively to explore biologic systems and elucidate cellular signaling pathways. In this study, we use an inhibitor of bacterial communication to monitor changes in the proteome of Salmonella enterica serovar Typhimurium with the aim of discovering unrecognized processes regulated by AI-2-based quorum-sensing (QS), a mechanism of bacterial intercellular communication that allows for the coordination of gene expression in a cell density-dependent manner. In S. typhimurium, this system regulates the uptake and catabolism of intercellular signals and has been implicated in pathogenesis, including the invasion of host epithelial cells. We demonstrate that our QS antagonist is capable of selectively inhibiting the expression of known QS-regulated proteins in S. typhimurium, thus attesting that QS inhibitors may be used to confirm proposed and elucidate previously unidentified QS pathways without relying on genetic manipulation.
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Affiliation(s)
- Colin A Lowery
- The Skaggs Institute for Chemical Biology, Departments of Chemistry, Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Proteome Analysis of the Two-Component SalK/SalR System in Epidemic Streptococcus suis Serotype 2. Curr Microbiol 2013; 67:118-22. [DOI: 10.1007/s00284-013-0343-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 02/12/2013] [Indexed: 11/26/2022]
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Eberl L, Riedel K. Mining quorum sensing regulated proteins - Role of bacterial cell-to-cell communication in global gene regulation as assessed by proteomics. Proteomics 2011; 11:3070-85. [PMID: 21548094 DOI: 10.1002/pmic.201000814] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 01/20/2011] [Accepted: 02/17/2011] [Indexed: 12/31/2022]
Affiliation(s)
- Leo Eberl
- Department of Microbiology, Institute of Plant Biology, University of Zürich, Zurich, Switzerland
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Di Cagno R, De Angelis M, Calasso M, Gobbetti M. Proteomics of the bacterial cross-talk by quorum sensing. J Proteomics 2011; 74:19-34. [DOI: 10.1016/j.jprot.2010.09.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 09/14/2010] [Accepted: 09/29/2010] [Indexed: 01/03/2023]
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Comparison of antigenic proteins from Lactococcus garvieae KG (−) and KG (+) strains that are recognized by olive flounder (Paralichthys olivaceus) antibodies. Vet Microbiol 2009; 139:113-20. [DOI: 10.1016/j.vetmic.2009.05.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Revised: 05/16/2009] [Accepted: 05/28/2009] [Indexed: 01/18/2023]
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Chun H, Choi O, Goo E, Kim N, Kim H, Kang Y, Kim J, Moon JS, Hwang I. The quorum sensing-dependent gene katG of Burkholderia glumae is important for protection from visible light. J Bacteriol 2009; 191:4152-7. [PMID: 19395481 PMCID: PMC2698513 DOI: 10.1128/jb.00227-09] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Accepted: 04/21/2009] [Indexed: 12/31/2022] Open
Abstract
Quorum sensing (QS) plays important roles in the pathogenicity of Burkholderia glumae, the causative agent of bacterial rice grain rot. We determined how QS is involved in catalase expression in B. glumae. The QS-defective mutant of B. glumae exhibited less catalase activity than wild-type B. glumae. A beta-glucuronidase assay of a katG::Tn3-gusA78 reporter fusion protein revealed that katG expression is under the control of QS. Furthermore, katG expression was upregulated by QsmR, a transcriptional activator for flagellar-gene expression that is regulated by QS. A gel mobility shift assay confirmed that QsmR directly activates katG expression. The katG mutant produced toxoflavin but exhibited less severe disease than BGR1 on rice panicles. Under visible light conditions and a photon flux density of 61.6 micromol(-1) m(-2), the survival rate of the katG mutant was 10(5)-fold lower than that of BGR1. This suggests that KatG is a major catalase that protects bacterial cells from visible light, which probably results in less severe disease caused by the katG mutant.
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Affiliation(s)
- Heejin Chun
- Department of Agricultural Biotechnology, Seoul National University, Seoul , Republic of Korea
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Kozlova EV, Popov VL, Sha J, Foltz SM, Erova TE, Agar SL, Horneman AJ, Chopra AK. Mutation in the S-ribosylhomocysteinase (luxS) gene involved in quorum sensing affects biofilm formation and virulence in a clinical isolate of Aeromonas hydrophila. Microb Pathog 2008; 45:343-54. [PMID: 18930130 DOI: 10.1016/j.micpath.2008.08.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2008] [Revised: 08/16/2008] [Accepted: 08/20/2008] [Indexed: 01/08/2023]
Abstract
A diarrheal isolate SSU of Aeromonas hydrophila produces a cytotoxic enterotoxin (Act) with cytotoxic, enterotoxic, and hemolytic activities. Our laboratory has characterized from the above Aeromonas strain, in addition to Act, the type 3- and T6-secretion systems and their effectors, as well as the genes shown to modulate the production of AI-1-like autoinducers, N-acylhomoserine lactones (AHLs) involved in quorum sensing (QS). In this study, we demonstrated the presence of an S-ribosylhomocysteinase (LuxS)-based autoinducer (AI)-2 QS system in A. hydrophila SSU and its contribution to bacterial virulence. The luxS isogenic mutant of A. hydrophila, which we prepared by marker exchange mutagenesis, showed an alteration in the dynamics and architecture of the biofilm formation, a decrease in the motility of the bacterium, and an enhanced virulence in the septicemic mouse model. Moreover, these effects of the mutation could be complemented. Enhanced production of the biofilm exopolysaccharide and filaments in the mutant strain were presumably the major causes of the observed phenotype. Our earlier studies indicated that the wild-type A. hydrophila with overproduction of DNA adenine methyltransferase (Dam) had significantly reduced motility, greater hemolytic activity associated with Act, and an enhanced ability to produce AI-1 lactones. Furthermore, such a Dam-overproducing strain was not lethal to mice. On the contrary, the luxS mutant with Dam overproduction showed an increased motility and had no effect on lactone production. In addition, the Dam-overproducing luxS mutant strain was not altered in its ability to induce lethality in a mouse model of infection when compared to the parental strain which overproduced Dam. We suggested that an altered gene expression in the luxS mutant of A. hydrophila SSU, as it related to biofilm formation and virulence, might be linked with the interruption of the bacterial metabolic pathway, specifically of methionine synthesis.
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Affiliation(s)
- Elena V Kozlova
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
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Li M, Wang C, Feng Y, Pan X, Cheng G, Wang J, Ge J, Zheng F, Cao M, Dong Y, Liu D, Wang J, Lin Y, Du H, Gao GF, Wang X, Hu F, Tang J. SalK/SalR, a two-component signal transduction system, is essential for full virulence of highly invasive Streptococcus suis serotype 2. PLoS One 2008; 3:e2080. [PMID: 18461172 PMCID: PMC2358977 DOI: 10.1371/journal.pone.0002080] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2007] [Accepted: 03/04/2008] [Indexed: 11/22/2022] Open
Abstract
Background Streptococcus suis serotype 2 (S. suis 2, SS2) has evolved into a highly infectious entity, which caused the two recent large-scale outbreaks of human SS2 epidemic in China, and is characterized by a toxic shock-like syndrome. However, the molecular pathogenesis of this new emerging pathogen is still poorly understood. Methodology/Principal Findings 89K is a newly predicted pathogenicity island (PAI) which is specific to Chinese epidemic strains isolated from these two SS2 outbreaks. Further bioinformatics analysis revealed a unique two-component signal transduction system (TCSTS) located in the candidate 89K PAI, which is orthologous to the SalK/SalR regulatory system of Streptococcus salivarius. Knockout of salKR eliminated the lethality of SS2 in experimental infection of piglets. Functional complementation of salKR into the isogenic mutant ΔsalKR restored its soaring pathogenicity. Colonization experiments showed that the ΔsalKR mutant could not colonize any susceptible tissue of piglets when administered alone. Bactericidal assays demonstrated that resistance of the mutant to polymorphonuclear leukocyte (PMN)-mediated killing was greatly decreased. Expression microarray analysis exhibited a transcription profile alteration of 26 various genes down-regulated in the ΔsalKR mutant. Conclusions/Significance These findings suggest that SalK/SalR is requisite for the full virulence of ethnic Chinese isolates of highly pathogenic SS2, thus providing experimental evidence for the validity of this bioinformatically predicted PAI.
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Affiliation(s)
- Ming Li
- Department of Microbiology, Third Military Medical University, Chongqing, China
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Changjun Wang
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Youjun Feng
- Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Graduate University, Chinese Academy of Sciences, Beijing, China
| | - Xiuzhen Pan
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Gong Cheng
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Jing Wang
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Junchao Ge
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Feng Zheng
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Min Cao
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Yaqing Dong
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
| | - Di Liu
- Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Jufang Wang
- Provincial Key Laboratory of Biotechnology, School of Biosciences & Bioengineering, South China University of Technology, Guangzhou, China
| | - Ying Lin
- Provincial Key Laboratory of Biotechnology, School of Biosciences & Bioengineering, South China University of Technology, Guangzhou, China
| | - Hongli Du
- Provincial Key Laboratory of Biotechnology, School of Biosciences & Bioengineering, South China University of Technology, Guangzhou, China
| | - George F. Gao
- Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xiaoning Wang
- Provincial Key Laboratory of Biotechnology, School of Biosciences & Bioengineering, South China University of Technology, Guangzhou, China
- * E-mail: (XW); (FH); (JT)
| | - Fuquan Hu
- Department of Microbiology, Third Military Medical University, Chongqing, China
- * E-mail: (XW); (FH); (JT)
| | - Jiaqi Tang
- Department of Microbiology, Third Military Medical University, Chongqing, China
- Department of Epidemiology, Research Institute for Medicine of Nanjing Command, Nanjing, China
- * E-mail: (XW); (FH); (JT)
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