801
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Zhou YY, Zhang HZ, Liang WL, Zhang LJ, Zhu J, Kan B. Plasticity of regulation of mannitol phosphotransferase system operon by CRP-cAMP complex in Vibrio cholerae. Biomed Environ Sci 2013; 26:831-840. [PMID: 24215877 DOI: 10.3967/bes2013.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 02/22/2013] [Indexed: 06/02/2023]
Abstract
OBJECTIVE The complex of the cyclic AMP receptor protein (CRP) and cAMP is an important transcriptional regulator of numerous genes in prokaryotes. The transport of mannitol through the phosphotransferase systems (PTS) is regulated by the CRP-cAMP complex. The aim of the study is to investigate how the CRP-cAMP complex acting on the mannitol PTS operon mtl of the Vibrio cholerae El Tor biotype. METHODS The crp mutant strain was generated by homologous recombination to assess the need of CRP to activate the mannitol PTS operon of V. cholerae El Tor. Electrophoretic mobility shift assays (EMSA) and the reporter plasmid pBBRlux were used to confirm the role that the CRP-cAMP complex playing on the mannitol PTS operon mtl. RESULTS In this study, we confirmed that CRP is strictly needed for the activation of the mtl operon. We further experimentally identified five CRP binding sites within the promoter region upstream of the mannitol PTS operon mtl of the Vibrio cholerae El Tor biotype and found that these sites display different affinities for CRP and provide different contributions to the activation of the operon. CONCLUSION The five binding sites collectively confer the strong activation of mannitol transfer by CRP in V. cholerae, indicating an elaborate and subtle CRP activation mechanism.
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Affiliation(s)
- Yan Yan Zhou
- State Key Laboratory for Communicable Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
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802
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Soli KW, Kas M, Maure T, Umezaki M, Morita A, Siba PM, Greenhill AR, Horwood PF. Evaluation of colorimetric detection methods for Shigella, Salmonella, and Vibrio cholerae by loop-mediated isothermal amplification. Diagn Microbiol Infect Dis 2013; 77:321-3. [PMID: 24157057 DOI: 10.1016/j.diagmicrobio.2013.09.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 09/12/2013] [Accepted: 09/15/2013] [Indexed: 12/18/2022]
Abstract
We evaluated loop-mediated isothermal amplification end-point detection methods for Salmonella, Shigella, and Vibrio cholerae. Detection sensitivities were comparable to real-time PCR methods. The colorimetric dyes hydroxynaphthol blue and SYBR Green I showed increased sensitivity when compared to visual and automated turbidity readings. End-point colorimetric dyes promise great utility in developing settings.
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803
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Chaivisuthangkura P, Pengsuk C, Longyant S, Sithigorngul P. Evaluation of monoclonal antibody based immunochromatographic strip test for direct detection of Vibrio cholerae O1 contamination in seafood samples. J Microbiol Methods 2013; 95:304-11. [PMID: 24060694 DOI: 10.1016/j.mimet.2013.09.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Revised: 09/11/2013] [Accepted: 09/12/2013] [Indexed: 10/26/2022]
Abstract
A strip test for the detection of Vibrio cholerae O1 was developed using two monoclonal antibodies (MAbs), VC-223 and VC-1226, specific to the lipopolysaccharides of Vibrio cholerae O1 Inaba and Ogawa serovars. The sensitivity of the test was 5 × 10(5)cfu/mL which was similar to that of dot blot test. The detection limit could be improved to 1cfu/mL of the original bacterial content after pre-incubation of the bacterium in alkaline peptone water (APW) for 12h. Detection of V. cholerae O1 in various fresh seafood samples such as shrimp, blood clam, mussel and oyster could be performed directly with sensitivities ranged from 5 × 10(5) to 10(6)cfu/mL. After pre-enrichment of the shrimp sample in APW, the detection sensitivities increased to 10(2) to 10CFU/mL of the original bacterial content after incubation for 12 and 24h. However, the detection sensitivities were also depending on the content of the other bacteria that might inhibit the growth of V. cholerae during pre-enrichment step. The V. cholerae O1 strip test has advantages in speed, and simplicity in not requiring sophisticated equipment or specialized skills and the sample could be directly examined without requirement for sample processing.
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804
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Peach KC, Cheng AT, Oliver AG, Yildiz FH, Linington RG. Discovery and biological characterization of the auromomycin chromophore as an inhibitor of biofilm formation in Vibrio cholerae. Chembiochem 2013; 14:2209-15. [PMID: 24106077 DOI: 10.1002/cbic.201300131] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Indexed: 11/06/2022]
Abstract
Bacterial biofilms pose a significant challenge in clinical environments due to their inherent lack of susceptibility to antibiotic treatment. It is widely recognized that most pathogenic bacterial strains in the clinical setting persist in the biofilm state, and are the root cause of many recrudescent infections. The discovery and development of compounds capable of either inhibiting biofilm formation or initiating biofilm dispersal might provide new therapeutic avenues for reducing the number of hospital-acquired, biofilm-mediated infections. We detail here the application of our recently reported image-based, high-throughput screen to the discovery of microbially derived natural products with inhibitory activity against Vibrio cholerae biofilm. Examination of a prefractionated library of microbially derived marine natural products has led to the identification of a new biofilm inhibitor that is structurally unrelated to previously reported inhibitors and is one of the most potent inhibitors of V. cholerae reported to date. Combination of this compound with sub-MIC concentrations of a number of clinically relevant antibiotics was shown to improve the inhibitory efficacy of this new compound compared to monotherapy treatments, and provides evidence for the potential therapeutic benefit of biofilm inhibitors in treating persistent biofilm-mediated infections.
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Affiliation(s)
- Kelly C Peach
- Department of Chemistry and Biochemistry, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (USA)
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805
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Wade WF, King RG, Grandjean C, Wade TK, Justement LB. Murine marginal zone B cells play a role in Vibrio cholerae LPS antibody responses. Pathog Dis 2013; 70:153-7. [PMID: 23966359 DOI: 10.1111/2049-632x.12085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/25/2013] [Accepted: 08/16/2013] [Indexed: 01/09/2023] Open
Abstract
The emergence of Vibrio cholerae (Vc) lipopolysaccharide (LPS) as a lead protective antigen for a cholera subunit vaccine has increased the interest in what type of B cell is best suited to generate anti-Vc LPS antibodies. A related question is what form of LPS is the most immunogenic. C57Bl/6 (B6) neonatal mice (10 days old) whose marginal zone (MZ) B cell compartment is still maturing and two lines of knockout mice that either lack the signaling mechanism required for the maturation of MZ B cells or that lack a receptor required for MZ B cell retention in the MZ were used to determine the role of MZ B cells in anti-Vc LPS antibody responses. Data support the conclusion that MZ B cells play a significant role in the anti-Vc LPS antibody response. Serum and vibriocidal antibody titers also depend on whether the Vc LPS is purified or bacterial cell-associated.
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Affiliation(s)
- William F Wade
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
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806
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Alizadeh J, Ranjbar R, Kamali M, Farhadi N, Davari A, Sadeghifard N. Cloning of Vibrio cholerae outer membrane protein W in Pichia pastoris. Iran J Microbiol 2013; 5:252-8. [PMID: 24475332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND OBJECTIVE The outer membrane protein W (ompW) of Vibrio cholerae is involved in stimulating the immune response via induction of protective immunity. It also plays an important role in bacterial pathogenesis by increasing the adaptability of pathogenic strains. In this study we aimed to clone V. cholerae ompW gene in the strain X-33 of Pichia pastoris. MATERIALS AND METHODS A gene encoding ompW was cloned into the Ppicza vector downstream of alcohol oxidase promoter. Then recombinant vector was transformed into the genome of the strain X-33 of P. pastoris. After growth of zeocin-resistant transformants, clones were selected and subsequently confirmed for cloning by PCR enzymatic digestion and sequencing. RESULTS PCR, enzymatic digestion and sequencing showed that the ompW gene was correctly cloned into P. pastoris genome. CONCLUSION Results of our study showed that the methylotrophic yeast P. pastoris can be considered as an appropriate host instead of mammalian and prokaryotic systems for cloning of ompW. As far as data show, this is the first time that ompW of V. cholera is cloned into the methylotrophic P. pastoris.
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807
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Ceccarelli D, Spagnoletti M, Hasan NA, Lansing S, Huq A, Colwell RR. A new integrative conjugative element detected in Haitian isolates of Vibrio cholerae non-O1/non-O139. Res Microbiol 2013; 164:891-893. [PMID: 23994142 DOI: 10.1016/j.resmic.2013.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 08/01/2013] [Indexed: 12/29/2022]
Abstract
The presence of SXT/R391-related integrating conjugative elements (ICEs) in Vibrio cholerae O1 and non-O1/non-O139 isolated from clinical and environmental samples in Haiti in 2010 was studied. The main finding of this work was the identification of the novel ICEVchHai2 among closely related V. cholerae non-O1/non-O139 clinical strains. The mosaic structure of this element confirms the role of ICEs as efficient recombination systems whereby new genetic material can be acquired and exchanged, according V. cholerae strains new accessory functions.
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Affiliation(s)
- Daniela Ceccarelli
- Maryland Pathogen Research Institute, University of Maryland, College Park, MD 20742, USA
| | - Matteo Spagnoletti
- University College London Genetics Institute, University College London, London WC1E 6BT, UK
| | - Nur A Hasan
- Maryland Pathogen Research Institute, University of Maryland, College Park, MD 20742, USA.,CosmosID Inc., College Park, MD 20742, USA
| | - Stephanie Lansing
- Department of Environmental Science and Technology, University of Maryland, College Park, MD 20742, USA
| | - Anwar Huq
- Maryland Pathogen Research Institute, University of Maryland, College Park, MD 20742, USA.,Maryland Institute of Applied Environmental Health, University of Maryland, College Park, MD 20742, USA
| | - Rita R Colwell
- Maryland Pathogen Research Institute, University of Maryland, College Park, MD 20742, USA.,CosmosID Inc., College Park, MD 20742, USA.,Maryland Institute of Applied Environmental Health, University of Maryland, College Park, MD 20742, USA.,Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
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808
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Dey S, Dasgupta J. Purification, crystallization and preliminary X-ray analysis of the AAA+ σ54 activator domain of FlrC from Vibrio cholerae. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:800-3. [PMID: 23832212 DOI: 10.1107/s1744309113015613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 06/04/2013] [Indexed: 11/10/2022]
Abstract
A σ(54)-dependent transcriptional activator FlrC containing an N-terminal regulatory domain, a central AAA(+) domain and a C-terminal DNA-binding domain has been implicated both in flagellar synthesis and enhanced intestinal colonization. FlrC is phosphorylated by the kinase FlrB at the regulatory domain and both nonphosphorylated and phosphorylated states of FlrC seem to be important for its functions. Oligomerization plays a key role in the functions of such transcriptional activators and the AAA(+) σ(54) interaction domain is critical in deciding the oligomerization state. Therefore, to obtain structural insights into FlrC at the atomic level, the AAA(+) σ(54) interaction domain of FlrC was cloned, overexpressed and crystallized using PEG 6000 as precipitant at pH 6.0, and diffraction data were collected to 2.8 Å resolution. Molecular-replacement calculations and subsequent refinement confirmed the presence of a closed heptamer in the asymmetric unit.
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Affiliation(s)
- Sanjay Dey
- Department of Biotechnology, St Xavier's College, 30 Park Street, Kolkata 700 016, India
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809
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Edwin A, Rompikuntal P, Björn E, Stier G, Wai SN, Sauer-Eriksson AE. Calcium binding by the PKD1 domain regulates interdomain flexibility in Vibrio cholerae metalloprotease PrtV. FEBS Open Bio 2013; 3:263-70. [PMID: 23905008 PMCID: PMC3722578 DOI: 10.1016/j.fob.2013.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 06/20/2013] [Accepted: 06/21/2013] [Indexed: 01/06/2023] Open
Abstract
Vibrio cholerae, the causative agent of cholera, releases several virulence factors including secreted proteases when it infects its host. These factors attack host cell proteins and break down tissue barriers and cellular matrix components such as collagen, laminin, fibronectin, keratin, elastin, and they induce necrotic tissue damage. The secreted protease PrtV constitutes one virulence factors of V. cholerae. It is a metalloprotease belonging to the M6 peptidase family. The protein is expressed as an inactive, multidomain, 102 kDa pre-pro-protein that undergoes several N- and C-terminal modifications after which it is secreted as an intermediate variant of 81 kDa. After secretion from the bacteria, additional proteolytic steps occur to produce the 55 kDa active M6 metalloprotease. The domain arrangement of PrtV is likely to play an important role in these maturation steps, which are known to be regulated by calcium. However, the molecular mechanism by which calcium controls proteolysis is unknown. In this study, we report the atomic resolution crystal structure of the PKD1 domain from V. cholera PrtV (residues 755–838) determined at 1.1 Å. The structure reveals a previously uncharacterized Ca2+-binding site located near linker regions between domains. Conformational changes in the Ca2+-free and Ca2+-bound forms suggest that Ca2+-binding at the PKD1 domain controls domain linker flexibility, and plays an important structural role, providing stability to the PrtV protein. The PKD1 domain was expressed in E. coli and purified to homogeneity. Purified PKD1 domains are not toxic for human HTC8 cells. The atomic 1.1 Å crystal structure of the PKD1 domain revealed a Ca2+-binding site. Ca2+ binding causes large conformational changes in the N-terminal half of the PKD1 domain. Ca2+ stabilizes the 81 kDa pro-protein outside the bacterial cell, preventing its degradation.
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Affiliation(s)
- Aaron Edwin
- Department of Chemistry, Umeå University, Umeå SE-901 87, Sweden
- Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå SE-901 87, Sweden
| | - Pramod Rompikuntal
- Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå SE-901 87, Sweden
- Department of Molecular Biology, Umeå University, Umeå SE-901 87, Sweden
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå SE-901 87, Sweden
| | - Erik Björn
- Department of Chemistry, Umeå University, Umeå SE-901 87, Sweden
| | - Gunter Stier
- Department of Chemistry, Umeå University, Umeå SE-901 87, Sweden
| | - Sun N. Wai
- Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå SE-901 87, Sweden
- Department of Molecular Biology, Umeå University, Umeå SE-901 87, Sweden
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå SE-901 87, Sweden
| | - A. Elisabeth Sauer-Eriksson
- Department of Chemistry, Umeå University, Umeå SE-901 87, Sweden
- Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå SE-901 87, Sweden
- Corresponding author at: Department of Chemistry, Umeå University, Umeå SE-901 87, Sweden. Tel.: +46 90 7865923; fax: +46 90 7865944.
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810
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Park JY, Jeon S, Kim JY, Park M, Kim S. Multiplex Real-time Polymerase Chain Reaction Assays for Simultaneous Detection of Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus. Osong Public Health Res Perspect 2013; 4:133-9. [PMID: 24159544 PMCID: PMC3787528 DOI: 10.1016/j.phrp.2013.04.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 03/25/2013] [Accepted: 04/05/2013] [Indexed: 12/03/2022] Open
Abstract
Objectives A multiplex real-time polymerase chain reaction (RT-PCR) method was developed for the identification of three Vibrio species: Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus. Methods Specific primers and probes targeting the hlyA, tlh, and vvhA genes were selected and used for multiplex real-time PCR to confirm the identification of V. cholerae, V. parahaemolyticus, and V. vulnificus, respectively. This method was applied to screen Vibrio species from environmental samples and combining it with a culture-based method, its effectiveness was evaluated in comparison with culture-based methods alone. Results Specific PCR fragments were obtained from isolates belonging to the target species, indicating a high specificity of this multiplex real-time PCR. No cross-reactivity with the assay was observed between the tested bacteria. The sensitivity of the multiplex real-time PCR was found to have a lower limit of 104 colony-forming units/reaction for all three Vibrio species. The combination strategy raised the isolation ratio of all three Vibrio species 1.26- to 2.75-fold. Conclusion This assay provides a rapid, sensitive, and specific technique to detect these three Vibrio species in the environment.
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Affiliation(s)
- Jie Yeun Park
- Division of Enteric Bacterial Infections, Korea National Institute of Health, Osong, Korea
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811
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Kolappan S, Craig L. Structure of the cytoplasmic domain of TcpE, the inner membrane core protein required for assembly of the Vibrio cholerae toxin-coregulated pilus. Acta Crystallogr D Biol Crystallogr 2013; 69:513-9. [PMID: 23519659 DOI: 10.1107/s0907444912050330] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 12/10/2012] [Indexed: 11/10/2022]
Abstract
Type IV pili are long thin surface-displayed polymers of the pilin subunit that are present in a diverse group of bacteria. These multifunctional filaments are critical to virulence for pathogens such as Vibrio cholerae, which use them to form microcolonies and to secrete the colonization factor TcpF. The type IV pili are assembled from pilin subunits by a complex inner membrane machinery. The core component of the type IV pilus-assembly platform is an integral inner membrane protein belonging to the GspF superfamily of secretion proteins. These proteins somehow convert chemical energy from ATP hydrolysis by an assembly ATPase on the cytoplasmic side of the inner membrane to mechanical energy for extrusion of the growing pilus filament out of the inner membrane. Most GspF-family inner membrane core proteins are predicted to have N-terminal and central cytoplasmic domains, cyto1 and cyto2, and three transmembrane segments, TM1, TM2 and TM3. Cyto2 and TM3 represent an internal repeat of cyto1 and TM1. Here, the 1.88 Å resolution crystal structure of the cyto1 domain of V. cholerae TcpE, which is required for assembly of the toxin-coregulated pilus, is reported. This domain folds as a monomeric six-helix bundle with a positively charged membrane-interaction face at one end and a hydrophobic groove at the other end that may serve as a binding site for partner proteins in the pilus-assembly complex.
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812
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De Bari H, Berry EA. Structure of Vibrio cholerae ribosome hibernation promoting factor. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:228-36. [PMID: 23519794 PMCID: PMC3606564 DOI: 10.1107/s1744309113000961] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 01/10/2013] [Indexed: 11/10/2022]
Abstract
The X-ray crystal structure of ribosome hibernation promoting factor (HPF) from Vibrio cholerae is presented at 2.0 Å resolution. The crystal was phased by two-wavelength MAD using cocrystallized cobalt. The asymmetric unit contained two molecules of HPF linked by four Co atoms. The metal-binding sites observed in the crystal are probably not related to biological function. The structure of HPF has a typical β-α-β-β-β-α fold consistent with previous structures of YfiA and HPF from Escherichia coli. Comparison of the new structure with that of HPF from E. coli bound to the Thermus thermophilus ribosome [Polikanov et al. (2012), Science, 336, 915-918] shows that no significant structural changes are induced in HPF by binding.
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Affiliation(s)
- Heather De Bari
- Biochemistry and Molecular Biology, SUNY Upstate Medical University, 750 E. Adams Avenue, Syracuse, NY 13210, USA
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813
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Jain M, Kushwah KS, Kumar P, Goel AK. Molecular Characterization of Vibrio cholerae O1 Reveals Continuous Evolution of Its New Variants in India. Indian J Microbiol 2013; 53:137-41. [PMID: 24426099 DOI: 10.1007/s12088-013-0372-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 02/04/2013] [Indexed: 10/27/2022] Open
Abstract
Vibrio cholerae, the causing agent of cholera is still a major health challenge in most of the developing countries. In this study, V. cholerae strains collected from different cholera outbreaks in India over a period of past 7 years were found to have various toxigenic, pathogenic and regulatory genes viz. ctxAB, zot, tcp, hlyA, ace, ompU, ompW, rfbO1, toxT and toxR. The biotype specific genes rstR and rtxC revealed the El Tor biotype in majority of the isolates. However, variants among the isolates were found having genotype of both the biotypes. Sequencing of ctxB gene revealed the presence of altered ctxB of classical biotype with additional variations in isolates of 2007. Mismatch amplification mutation assay PCR also confirmed the isolates belonging to classical biotype. Antibiogram of the isolates revealed resistance for nalidixic acid, co-trimoxazole, streptomycin, and polymyxin B and susceptibility for tetracycline among most of the isolates from India. However, V. cholerae isolates from a recent outbreak in Eastern India were resistant to tetracycline. The study corroborated the continuous emergence and wide-spread of multidrug resistant El Tor variant strains in the Indian subcontinent.
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814
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Rivera ING, Souza KMC, Souza CP, Lopes RM. Free-living and plankton-associated vibrios: assessment in ballast water, harbor areas, and coastal ecosystems in Brazil. Front Microbiol 2013; 3:443. [PMID: 23335920 PMCID: PMC3544075 DOI: 10.3389/fmicb.2012.00443] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 12/26/2012] [Indexed: 12/03/2022] Open
Abstract
Ballast water (BW) is a major transport vector of exotic aquatic species and pathogenic microorganisms. The wide-ranging spread of toxigenic Vibrio cholerae O1 from harbor areas has been frequently ascribed to discharge of contaminated BW into eutrophic coastal environments, such as during the onset of the seventh cholera pandemic in South America in the early 1990s. To determine the microbiological hazards of BWs transported to Brazilian ports, we evaluated water and plankton samples taken from (i) BW tanks of recently arrived ships, (ii) port areas along the Brazilian coastline from ∼1 to 32°S and (iii) three coastal areas in São Paulo State. Vibrio concentration and toxigenic V. cholerae O1 occurrence were analyzed. Plankton-associated vibrios were more abundant than free-living vibrios in all studied environments. V. cholerae was found in 9.5% of ballast tanks and 24.2% of port samples, both as free-living and attached forms and, apart from the Santos harbor, was absent off São Paulo State. Toxigenic V. cholerae O1 isolates (ctxA+, tcpA+), involved in cholera disease, were found in BW (2%) and harbor (2%) samples. These results confirm that BW is an important carrier of pathogenic organisms, and that monitoring of vibrios and other plankton-attached bacteria is of paramount importance in BW management programs.
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Affiliation(s)
- Irma N G Rivera
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo São Paulo, Brazil
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815
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Amin Marashi SM, Rajabnia R, Imani Fooladi AA, Hojati Z, Moghim S, Nasr Esfahani B. Determination of ctxAB expression in Vibrio cholerae Classical and El Tor strains using Real-Time PCR. Int J Mol Cell Med 2013; 2:9-13. [PMID: 24551784 PMCID: PMC3920520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 03/18/2013] [Indexed: 10/30/2022]
Abstract
Cholera is an infection of the small intestines caused by the bacterium V. cholerae. It is a major cause of health threat and also a major cause of death worldwide and especially in developing countries. The major virulence factor produced by V. cholerae during infection is the cholera toxin. Total mRNA extraction and reverse transcription was performed for making ctxAB cDNA. Relative Real-Time PCR analysis showed unequal enterotoxin production in V. cholerae strains. The results showed that, classical strain produces cholera toxin more than El Tor strain.
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Affiliation(s)
- Seyed Mahmoud Amin Marashi
- Cellular and Molecular Biology Research Center, (CMBRC), Babol University of Medical Sciences, Babol, Iran.,Department of Microbiology and Immunology, Babol University of Medical Sciences, Babol, Iran.
| | - Ramazan Rajabnia
- Infectious Diseases & Tropical Medicine ResearchCenter, Babol University of Medical Sciences, Babol, Iran.
| | - Abbas Ali Imani Fooladi
- Applied Microbiology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
| | - Zohreh Hojati
- Genetics Division, Biology Department, Faculty of Sciences, University of Isfahan, Isfahan, Iran.
| | - Sharareh Moghim
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Bahram Nasr Esfahani
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.,Corresponding author: Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
E-Mail: .
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816
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Abstract
Understanding the genetic and ecological factors which support the emergence of new clones of pathogenic bacteria is vital to develop preventive measures. Vibrio cholerae the causative agent of cholera epidemics represents a paradigm for this process in that this organism evolved from environmental non-pathogenic strains by acquisition of virulence genes. The major virulence factors of V. cholerae, cholera toxin (CT) and toxin coregulated pilus (TCP) are encoded by a lysogenic bacteriophage (CTXφ) and a pathogenicity island, respectively. Additional phages which cooperate with the CTXφ in horizontal transfer of genes in V. cholerae have been characterized, and the potential exists for discovering yet new phages or genetic elements which support the transfer of genes for environmental fitness and virulence leading to the emergence of new epidemic strains. Phages have also been shown to play a crucial role in modulating seasonal cholera epidemics. Thus, the complex array of natural phenomena driving the evolution of pathogenic V. cholerae includes, among other factors, phages that either participate in horizontal gene transfer or in a bactericidal selection process favoring the emergence of new clones of V. cholerae.
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Affiliation(s)
- Shah M Faruque
- Centre for Food and Waterborne Diseases, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh.
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817
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Uchiyama H. Distribution of vibrio species isolated from aquatic environments with TCBS agar. Environ Health Prev Med 2000; 4:199-204. [PMID: 21432485 DOI: 10.1007/BF02931258] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/1998] [Accepted: 09/20/1999] [Indexed: 12/19/2022] Open
Abstract
Environmental bacteria grown on TCBS agar plates (TCBS strains) were investigated for the presence ofVibrio cholerae in aquatic environments. TCBS strain counts were 0.01 - 0.001 times the total viable counts in pairs of the same samples. The TCBS strains were of two types which required N(a)Cl (salt strain) and did not require N(a)Cl (non-salt strain) to grow in peptone water. Non-salt strains made up 85.3 - 92.1% of TCBS strains isolated from river water. TCBS strains isolated from an estuary contained 40.9% of non-salt strains and 57.4% of salt strains. Salt strains made up 69.2 - 86.8% of TCBS strains isolated from seawater. The percentages ofVibrio species in TCBS strains were 11.9 - 47.9%. V.alginolyticus andV. parahaemolyticus were isolated from seawater.V. vulnificus was only isolated from estuary water.V. cholerae non-Ol was isolated from both river water and estuary water which had low salinity.V. fluvialis was isolated from all three aquatic environments. This investigation suggests thatVibrio species were present in each sample station and thatV. cholerae existed in river water.
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818
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VidyaLaxme B, Rovetto A, Grau R, Agrawal R. Synergistic effects of probiotic Leuconostoc mesenteroides and Bacillus subtilis in malted ragi (Eleucine corocana) food for antagonistic activity against V. cholerae and other beneficial properties. J Food Sci Technol 2014; 51:3072-82. [PMID: 26396299 DOI: 10.1007/s13197-012-0834-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 08/21/2012] [Accepted: 08/23/2012] [Indexed: 10/27/2022]
Abstract
Finger millet (Elucine corocana), locally known as ragi, and probiotics have been recognized for their health benefits. In the present work we describe novel probiotic ragi malt (functional food) that has been prepared using ragi and probiotic Leuconostoc mesenteroides (Lm) and Bacillus subtilis natto (Bs), alone and in combination, for antagonistic activity against Vibrio cholerae (Vc). In vitro studies using pure cultures showed that each probiotic strain (Lm or Bs) was able to inhibit the planktonic growth of Vc as well as its ability to make biofilms and adhere to extracellular matrix proteins (fibronectin, Fn) that may function in vivo as initial ports of entrance of the pathogen. Interestingly, the combination of both probiotic strains (Lm plus Bs) produced the strongest activity against the Vc. When both cultures were used together in the ragi malt the antimicrobial activity against Vc was enhanced due to synergistic effect of both probiotic strains. The inclusion of both probiotic strains in the functional food produced higher amounts of beneficial fatty acids like linoleic and linolenic acid and increased the mineral content (iron and zinc). The viability and activity of Lm and Bs against Vc was further enhanced with the use of adjuvants like ascorbic acid, tryptone, cysteine hydrochloride and casein hydrolysate in the ragi malt. In sum, the intake of probiotic ragi malt supplemented with Lm and Bs may provide nutrition, energy, compounds of therapeutic importance and antagonistic activity against Vc to a large extent to the consumer.
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819
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Adagbada AO, Adesida SA, Nwaokorie FO, Niemogha MT, Coker AO. Cholera epidemiology in Nigeria: an overview. Pan Afr Med J 2012; 12:59. [PMID: 22937199 PMCID: PMC3428179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 06/04/2012] [Indexed: 11/23/2022] Open
Abstract
Cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the bacterium, Vibrio cholera. Choleragenic V. cholera O1 and O139 are the only causative agents of the disease. The two most distinguishing epidemiologic features of the disease are its tendency to appear in explosive outbreaks and its predisposition to causing pandemics that may progressively affect many countries and spread into continents. Despite efforts to control cholera, the disease continues to occur as a major public health problem in many developing countries. Numerous studies over more than a century have made advances in the understanding of the disease and ways of treating patients, but the mechanism of emergence of new epidemic strains, and the ecosystem supporting regular epidemics, remain challenging to epidemiologists. In Nigeria, since the first appearance of epidemic cholera in 1972, intermittent outbreaks have been occurring. The later part of 2010 was marked with severe outbreak which started from the northern part of Nigeria, spreading to the other parts and involving approximately 3,000 cases and 781 deaths. Sporadic cases have also been reported. Although epidemiologic surveillance constitutes an important component of the public health response, publicly available surveillance data from Nigeria have been relatively limited to date. Based on existing relevant scientific literature on features of cholera, this paper presents a synopsis of cholera epidemiology emphasising the situation in Nigeria.
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Affiliation(s)
- Ajoke Olutola Adagbada
- Molecular Biology and Biotechnology Division, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria
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820
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Marashi SMA, Nasr Esfahani B, Tavakoli A, Moghim S, Pourshafie MR, Salehi M. Simultaneous Detection of Integrase and Antibiotic Resistance Genes within SXT Constin in Vibrio cholerae O1 El Tor Strains Isolated from Iran Using Multiplex-PCR. Iran J Basic Med Sci 2012; 15:885-9. [PMID: 23493053 PMCID: PMC3586891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 06/07/2011] [Indexed: 11/17/2022]
Abstract
OBJECTIVES Amongst the various antibiotic resistant elements in Vibrio. cholerae, SXT constin (SXT-C) is important. We were going to design a quick method for determination of antibiotic resistance gene pattern in SXT-C. MATERIALS AND METHODS Ninety four V. cholerae O1 El Tor isolates were used in this study. Antibiotic susceptibility testing, multiplex PCR amplification of SXT-C containing dfrA1, sulII, strB and the int in a multiplex PCR were done. RESULTS Results of our study showed that 92 (97.8%) out of 94 isolates were positive for all above genes. Multiplex PCR results correlated with the antibiotic susceptibility data obtained by using disc diffusion assay. CONCLUSION Using this multiplex PCR, it would be easily possible to demonstrate the presence of antibiotic resistance in SXT-C which, in turn, allows for a suitable treatment in cholera patients causing reduction in the mortality and morbidity rate of the infected individuals.
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Affiliation(s)
| | - Bahram Nasr Esfahani
- Department of Microbiology, Isfahan University of Medical Sciences, Isfahan, Iran,Corresponding author: Tel/Fax: +98-311-7922438;
| | - Akbar Tavakoli
- Department of Microbiology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sharareh Moghim
- Department of Microbiology, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Mansoor Salehi
- Departments of Genetics, Isfahan University of Medical Sciences, Isfahan, Iran
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821
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Anvari S, Najar Peerayeh S, Behmanesh M, Boustanshenas M. Biological activity of recombinant accessory cholerae enterotoxin (ace) on rabbit ileal loops and antibacterial assay. Cell J 2012; 14:209-14. [PMID: 23507621 PMCID: PMC3584440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 02/22/2012] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Vibrio cholerae (V. cholerae) causes a potentially lethal disease named cholera. The cholera enterotoxin (CT) is a major virulence factor of V. cholerae. In addition to CT, V. cholerae produces other putative toxins, such as the zonula occludens toxin (Zot) and accessory cholera enterotoxin (Ace). The ace gene is the third gene of the V. cholerae virulence cassette. The Ace toxin alters ion transport, causes fluid accumulation in ligated rabbit ileal loops, and is a cause of mild diarrhea. The aim of this study is the cloning and overexpression of the ace gene into Escherichia coli (E. coli) and determination of some characteristics of the recombinant Ace protein. MATERIALS AND METHODS In this experimental study, the ace gene was amplified from V. cholerae strain 62013, then cloned in a pET28a expression vector and transformed into an E. coli (DH5 α) host strain. Subsequently, the recombinant vector was retransformed into E. coli BL21 for expression, induced by isopropythio-β-D-galctoside (IPTG) at a different concentration, and examined by SDS-PAGE and Western blot. A rabbit ileal loop experiment was conducted. Antibacterial activity of the Ace protein was assessed for E. coli, Stapylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa). RESULTS The recombinant Ace protein with a molecular weight of 18 kDa (dimeric form) was expressed in E. coli BL21. The Ace protein showed poor staining with Coomassie blue stain, but stained efficiently with silver stain. Western blot analysis showed that the recombinant Ace protein reacted with rabbit anti-V. cholerae polyclonal antibody. The Ace protein had antibacterial activity at a concentration of ≥200 µg/ml and caused significant fluid accumulation in the ligated rabbit ileal loop test. CONCLUSION This study described an E. coli cloning and expression system (E. coli BL21- pET-28a-ace) for the Ace protein of V. cholerae. We confirmed the antibacterial properties and enterotoxin activity of the resultant recombinant Ace protein.
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Affiliation(s)
- Shaghayegh Anvari
- 1. Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Shahin Najar Peerayeh
- 1. Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran, * Corresponding Address:
P.O.Box: 331-14115Department of BacteriologyFaculty of Medical SciencesTarbiat Modares UniversityTehranIran
| | - Mehrdad Behmanesh
- 2. Department of Genetics, Faculty of Basic Sciences, Tarbiat Modares University, Tehran, Iran
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822
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Alam M, Islam A, Bhuiyan NA, Rahim N, Hossain A, Khan GY, Ahmed D, Watanabe H, Izumiya H, Faruque ASG, Akanda AS, Islam S, Sack RB, Huq A, Colwell RR, Cravioto A. Clonal transmission, dual peak, and off-season cholera in Bangladesh. Infect Ecol Epidemiol 2011; 1:IEE-1-7273. [PMID: 22957115 PMCID: PMC3426334 DOI: 10.3402/iee.v1i0.7273] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/22/2011] [Accepted: 07/04/2011] [Indexed: 12/04/2022] Open
Abstract
Vibrio cholerae is an estuarine bacterium associated with a single peak of cholera (March–May) in coastal villages of Bangladesh. For an unknown reason, however, cholera occurs in a unique dual peak (March–May and September–November) pattern in the city of Dhaka that is bordered by a heavily polluted freshwater river system and flood embankment. In August 2007, extreme flooding was accompanied by an unusually severe diarrhea outbreak in Dhaka that resulted in a record high illness. This study was aimed to understand the unusual outbreak and if it was related to the circulation of a new V. cholerae clone. Nineteen V. cholerae isolated during the peak of the 2007 outbreak were subjected to extensive phenotypic and molecular analyses, including multi-locus genetic screening by polymerase chain reaction (PCR), sequence-typing of the ctxB gene, and pulsed-field gel electrophoresis (PFGE). Factors associated with the unusual incidence of cholera were determined and analysis of the disease severity was done. Overall, microbiological and molecular data confirmed that the hypervirulent V. cholerae was O1 biotype El Tor (ET) that possessed cholera toxin (CT) of the classical biotype. The PFGE (NotI) and dendrogram clustering confirmed that the strains were clonal and related to the pre-2007 variant ET from Dhaka and Matlab and resembled one of two distinct clones of the variant ET confirmed to be present in the estuarine ecosystem of Bangladesh. Results of the analyses of both diarrheal case data for three consecutive years (2006–2008) and regional hydroclimatology over three decades (1980–2009) clearly indicate that the pattern of cholera occurring in Dhaka, and not seen at other endemic sites, was associated with flood waters transmitting the infectious clone circulating via the fecal-oral route during and between the dual seasonal cholera peaks in Dhaka. Circular river systems and flood embankment likely facilitate transmission of infectious V. cholerae throughout the year that leads to both sudden and off-season outbreaks in the densely populated urban ecosystem of Dhaka. Clonal recycling of hybrid El Tor with increasing virulence in a changing climate and in a region with a growing urban population represents a serious public health concern for Bangladesh.
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Affiliation(s)
- Munirul Alam
- Centre for Food and Waterborne Disease, International Center for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
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823
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Tsou AM, Frey EM, Hsiao A, Liu Z, Zhu J. Coordinated regulation of virulence by quorum sensing and motility pathways during the initial stages of Vibrio cholerae infection. Commun Integr Biol 2011; 1:42-4. [PMID: 19704787 DOI: 10.4161/cib.1.1.6662] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 07/24/2008] [Indexed: 11/19/2022] Open
Abstract
Pathogenic bacteria, such as Vibrio cholerae, must be capable of adapting to diverse living conditions, especially when transitioning from life in environmental reservoirs to life in a host. The abilities to sense arrival at a site suitable for colonization or infection and to respond with appropriate alterations in gene expression are crucial for a pathogen's success. Recently, we have shown that V. cholerae is able to recognize that it has reached its colonization site in the small intestine by sensing breakage of its flagellum as it penetrates the mucosal layer overlaying the intestinal epithelium. Flagellar loss results in the release of the anti-sigma factor FlgM and subsequent activation of the alternative sigma-factor FliA. FliA represses the quorum sensing-controlled transcriptional regulator, HapR, allowing increased expression of virulence factors such as Cholera Toxin (CT) and the Toxin Coregulated Pilus (TCP). In this way, the de-repression of virulence factor expression coincides with the arrival of bacteria at the site of infection at the intestinal mucosa. Our work reveals an interesting interplay between motility and quorum sensing signaling pathways to precisely time virulence gene expression during colonization.
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Affiliation(s)
- Amy M Tsou
- Department of Microbiology; University of Pennsylvania School of Medicine; Philadelphia, Pennsylvania USA
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824
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Madhusudana RB, Surendran PK. Detection of ctx gene positive non-O1/non-O139 V. cholerae in shrimp aquaculture environments. J Food Sci Technol 2013; 50:496-504. [PMID: 24425944 DOI: 10.1007/s13197-011-0374-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 03/28/2011] [Accepted: 04/06/2011] [Indexed: 10/18/2022]
Abstract
Water and post-larvae samples from black tiger (Penaeus monodon) shrimp hatcheries; pond water, pond sediment and shrimp from aquaculture farms were screened for the presence of V. cholerae. A V. cholerae-duplex PCR method was developed by utilizing V. cholerae species specific sodB primers and ctxAB genes specific primers. Incidence of V. cholerae was not observed in shrimp hatchery samples but was noticed in aquaculture samples. The incidence of V. cholerae was higher in pond water (7.6%) than in pond sediment (5.2%). Shrimp head (3.6%) portion had relatively higher incidence than shrimp muscle (1.6%). All the V. cholerae isolates (n = 42) belonged to non-O1/non-O139 serogroup, of which 7% of the V. cholerae isolates were potentially cholera-toxigenic (ctx positive). All the ctx positive V. cholerae (n = 3) were isolated from the pond water. Since, cholera toxin (CT) is the major contributing factor for cholera gravis, it is proposed that the mere presence of non-O1/non-O139 V. cholerae need not be the biohazard criterion in cultured black tiger shrimp but only the presence of ctx carrying non-O1/non-O139 V. cholerae may be considered as potential public health risk.
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825
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Shamini G, Ravichandran M, Sinnott JT, Somboonwit C, Sidhu HS, Shapshak P, Kangueane P. Structural inferences for Cholera toxin mutations in Vibrio cholerae. Bioinformation 2011; 6:1-9. [PMID: 21464837 PMCID: PMC3064844 DOI: 10.6026/97320630006001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 02/01/2011] [Indexed: 11/23/2022] Open
Abstract
Cholera is a global disease that has persisted for millennia. The cholera toxin (CT) from Vibrio cholerae is responsible for the clinical symptoms of cholera. This toxin is a hetero-hexamer (AB(5)) complex consisting of a subunit A (CTA) with a pentamer (B(5)) of subunit B (CTB). The importance of the AB(5) complex for pathogenesis is established for the wild type O1 serogroup using known structural and functional data. However, its role is not yet documented in other known serogroups harboring sequence level residue mutations. The sequences for the toxin from different serogroups are available in GenBank (release 177). Sequence analysis reveals mutations at several sequence positions in the toxin across serogroups. Therefore, it is of interest to locate the position of these mutations in the AB(5) structure to infer complex assembly for its functional role in different serogroups. We show that mutations in the CTA are at the solvent exposed regions of the AB(5) complex, whereas those in the CTB are at the CTB/CTB interface of the homo-pentamer complex. Thus, the role of mutations at the CTB/CTB interface for B(5) complex assembly is implied. It is observed that these mutations are often non-synonymous (e.g. polar to non-polar or vice versa). The formation of the AB(5) complex involves inter-subunit residue-residue interactions at the protein-protein interfaces. Hence, these mutations, at the structurally relevant positions, are of importance for the understanding of pathogenesis by several serogroups. This is also of significance in the improvement of recombinant CT protein complex analogs for vaccine design and their use against multiple serogroups.
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Affiliation(s)
- Gunasagaran Shamini
- Department of Biotechnology, AIMST University, Semeling 08100, Kedah, Malaysia
- Biomedical Informatics, Pondicherry, India 607402
| | | | - John T Sinnott
- Division of Infectious Disease, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida 33606, USA
- Clinical Research Unit, Hillsborough Health Department,Tampa, Florida 33602, USA
| | - Charurut Somboonwit
- Division of Infectious Disease, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida 33606, USA
- Clinical Research Unit, Hillsborough Health Department,Tampa, Florida 33602, USA
| | - Harcharan S Sidhu
- Department of Biotechnology, AIMST University, Semeling 08100, Kedah, Malaysia
| | - Paul Shapshak
- Division of Infectious Disease, Department of Internal Medicine, Tampa General Hospital, University of South Florida, College of Medicine, Tampa, Florida 33606, USA
- Department of Psychiatry and Behavioral Medicine, University of South Florida, College of Medicine, Tampa, Florida 33613, USA
| | - Pandjassarame Kangueane
- Department of Biotechnology, AIMST University, Semeling 08100, Kedah, Malaysia
- Biomedical Informatics, Pondicherry, India 607402
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826
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Miyata ST, Kitaoka M, Wieteska L, Frech C, Chen N, Pukatzki S. The Vibrio Cholerae Type VI Secretion System: Evaluating its Role in the Human Disease Cholera. Front Microbiol 2010; 1:117. [PMID: 21607085 PMCID: PMC3095397 DOI: 10.3389/fmicb.2010.00117] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2010] [Accepted: 10/06/2010] [Indexed: 01/11/2023] Open
Abstract
Vibrio cholerae, the marine bacterium responsible for the diarrheal disease cholera, utilizes a multitude of virulence factors to cause disease. The importance of two of these factors, the toxin co-regulated pilus (TCP) and cholera toxin (CT), has been well documented for pandemic O1 and epidemic O139 serogroups. In contrast, endemic non-O1 and non-O139 serogroups can cause localized outbreaks of cholera-like illness, often in the absence of TCP and CT. One virulence mechanism used by these strains is the type VI secretion system (T6SS) to export toxins across the cell envelope and confer toxicity toward eukaryotic and prokaryotic organisms. The V. cholerae strain V52 (an O37 serogroup strain) possesses a constitutively active T6SS and was responsible for an outbreak of gastroenteritis in Sudan in 1968. To evaluate a potential role of the T6SS in the disease cholera, we compared the T6SS clusters of V. cholerae strains with sequenced genomes. We found that the majority of V. cholerae strains, including one pandemic strain, contain intact T6SS gene clusters; thus, we propose that the T6SS is a conserved mechanism that allows pandemic and endemic V. cholerae to persist both in the host and in the environment.
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Affiliation(s)
- Sarah T Miyata
- Department of Medical Microbiology and Immunology, University of Alberta Edmonton, AB, Canada
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827
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Tamrakar AK, Jain M, Goel AK, Kamboj DV, Singh L. Characterization of Vibrio cholerae from deep ground water in a cholera endemic area in Central India. Indian J Microbiol 2009; 49:271-5. [PMID: 23100781 DOI: 10.1007/s12088-009-0043-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 09/09/2008] [Indexed: 11/30/2022] Open
Abstract
A total of 8 out of 11 deep ground water samples collected from different villages in Central India were found contaminated with Vibrio cholerae non O1, non O139. In a multiplex PCR, isolates were found positive for ompW gene but negative for ctxAB and rfbO1 genes. However, isolates from two places were positive for tcp and zot genes, indicating their intestinal colonization and toxigenic potential. Antibiotic susceptibility studies revealed that all isolates were multidrug resistant. Although, none of the isolates was found PCR positive for the mobile genetic elements, class 1 integrons and SXT constins. The results of this study corroborated that deep ground water can also be an important reservoir of V. cholerae in plane endemic areas, suggesting a continuous monitoring of water samples for timely prevention of the disease.
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Affiliation(s)
- Akhilesh K Tamrakar
- Division of Biochemistry, Central Drug Research Institute, Lucknow, 226 001 India
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828
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Kingston JJ, Thavachelvam K, Tuteja U, James T, Janardhanan B, Batra HV. Antimicrobial susceptibility and molecular characterization of Vibrio cholerae from cholera outbreaks in Chennai. Indian J Microbiol 2009; 49:84-8. [PMID: 23100755 DOI: 10.1007/s12088-009-0007-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Accepted: 04/29/2008] [Indexed: 11/28/2022] Open
Abstract
The genotype and antibiotic resistance pattern of the toxigenic Vibrio cholerae strains associated with cholera outbreaks vary frequently. Fifty-one V. cholerae strains isolated from cholera outbreaks in Chennai (2002-2005) were screened for the presence of virulence and regulatory genes by multiplex polymerase chain reaction (PCR) assay. Genotyping of the isolates was done by VC1 primers derived from enterobacterial repetitive intergenic consensus (ERIC)-related sequence in V. cholerae. All the isolates possessed toxigenic genes, such as ctxA, ctxB, tcpA, ace, ompU, toxR and zot. Two different El Tor genotypes and one O139 genotype could be delineated by VC1-PCR. One of the El Tor genotypes was similar to the El Tor strains isolated from Bhind district and Delhi during 2004. Antibiotic susceptibility testing revealed greater variability among the isolates tested. All the isolates were found to be susceptible to norfloxacin, ciprofloxacin and tetracycline. Thiry-three per cent of the isolates were found to be resistant to more than 4 antibiotics and could be termed as multiple antibiotic resistant. Coexistence of O139 serogroup along with the El Tor biotype could be identified among the strains recovered during the period 2002-2004. The O139 isolates were found to be more susceptible to the antibiotics tested when compared to the El Tor isolates.
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Affiliation(s)
- J J Kingston
- Division of Microbiology, Defence Food Research Laboratory, Sidhartha Nagar, Mysore, Karnataka India
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829
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Bakhshi B, Pourshafie MR, Navabakbar F, Tavakoli A, Shahcheraghi F, Salehi M, Faradjzadegan Z, Zahraei SM. Comparison of distribution of virulence determinants in clinical and environmental isolates of Vibrio cholera. Iran Biomed J 2008; 12:159-165. [PMID: 18762819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
BACKGROUND The virulence of a pathogenic Vibrio cholerae is dependent on a discrete set of genetic determinants. In this study, we determined the distribution of virulence determinants among the clinical and environmental isolates of V. cholerae. METHODS The antibiotic resistance profiles of the isolates were determined using standard disk diffusion assay. PCR assay was performed to analyze the presence of toxin genes of ctx, zot and ace. The composition of cholera toxin encoding element (CTX) region flanking of the V. cholerae isolates was also analyzed. RESULTS All of the clinical isolates (100%) showed a complete set of virulence genes and also the attachment site of the filamentous bacteriophage CTXphi. None of the environmental isolates contained the virulence genes and the attachment site of the CTXphi. Analysis of the flanking regions including the toxin-linked cryptic element and repeat in toxin genes revealed their integrity in the clinical isolates while in the environmental isolates they were absent or contained incomplete sequences. Comparison of the antibiotic resistance assay of the environmental and clinical isolates showed a significant difference in the resistance profiles of the isolates obtained from the two sites. High rates of resistance to co-trimoxosol, streptomycin and chloramphenicol were found with clinical isolates. CONCLUSION The absence of all virulence determinants in the environmental strains may suggest that certain ecological features must be present for V. cholerae to acquire a complete set of virulence determinants and to turn them into pathogenic strains.
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Affiliation(s)
- Bita Bakhshi
- Department of Bacteriology, Pasteur Institute of Iran, Pasteur Ave., Tehran, Iran
- Faculty of Medicine, Isfahan University of Medical Sciences, Hezarjerib Ave., Isfahan, Iran
| | | | - Farahtaj Navabakbar
- Faculty of Medicine, Isfahan University of Medical Sciences, Hezarjerib Ave., Isfahan, Iran
| | - Akbar Tavakoli
- Faculty of Medicine, Isfahan University of Medical Sciences, Hezarjerib Ave., Isfahan, Iran
| | | | - Mansoor Salehi
- Faculty of Medicine, Isfahan University of Medical Sciences, Hezarjerib Ave., Isfahan, Iran
| | - Ziba Faradjzadegan
- Faculty of Medicine, Isfahan University of Medical Sciences, Hezarjerib Ave., Isfahan, Iran
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Goel AK, Bhadauria S, Kumar P, Kamboj DV, Singh L. Semi-nested polymerase chain reaction for detection of toxigenic Vibrio cholerae from environmental water samples. Indian J Microbiol 2007; 47:207-11. [PMID: 23100668 DOI: 10.1007/s12088-007-0041-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Revised: 06/11/2007] [Accepted: 07/05/2007] [Indexed: 01/17/2023] Open
Abstract
A rapid and sensitive direct cell semi-nested PCR assay was developed for the detection of viable toxigenic V. cholerae in environmental water samples. The semi-nested PCR assay amplified cholera toxin (ctxA2B) gene present in the toxigenic V. cholerae. The detection sensitivity of direct cell semi-nested PCR was 2 × 10(3) CFU of V. cholerae whereas direct cell single-step PCR could detect 2 × 10(4) CFU of V. cholerae. The performance of the assay was evaluated using environmental water samples after spiking with known number of Vibrio cholerae O1. The spiked water samples were filtered through a 0.22 micrometer membrane and the bacteria retained on filters were enriched in alkaline peptone water and then used directly in the PCR assay. The semi-nested PCR procedure coupled with enrichment could detect less than 1 CFU/ml in ground water and sea water whereas 2 CFU/ml and 20 CFU/ml could be detected in pond water and tap water, respectively. The proposed method is simple, faster than the conventional detection assays and can be used for screening of drinking water or environmental water samples for the presence of toxigenic V. cholerae.
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Affiliation(s)
- Ajay Kumar Goel
- Biotechnology Division, Defence Research & Development Establishment, Gwalior, 474 002 (M.P.) India
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