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Volume 147, Issue 4

Analysis of the role of flagellar activity in virulence gene expression in Free

Abstract

Expression of virulence factors and motility of are intimately linked by an as yet uncharacterized mechanism. Several lines of evidence indicate that the activity of the flagellum of might have an impact on virulence gene regulation, as alterations of the motility phenotype, either by mutation or by inhibitory drugs, result in varied levels of virulence factor production. The Na-driven polar flagella of some species are proposed to act as mechanosensors, sensing media viscosity. It has been suggested that the flagellum might act as a ‘voltmeter’, responding to changes in membrane potential, or might sense some environmental conditions that lead to the repression of virulence factors in . To test these hypotheses, β-galactosidase levels of several types of non-motile mutant derivatives of a :: reporter strain were analysed following changes in media viscosity, membrane potential and other environmental conditions. Like the parental strain, the non-motile strain showed increased :: expression in high-viscosity media, suggesting that the sensing of media viscosity does not occur via the flagella. Other molecules that might be able to detect changes in media viscosity could include mechanosensitive (MS) ion channels found in the bacterial membrane. However, a derivative strain mutated in two putative MS channels still showed increased :: expression in high-viscosity media, indicating that these putative ion channels of are not involved in the viscosity effect and suggesting an as yet uncharacterized mechanism for sensing of media viscosity. The flagellum does not appear to act as a voltmeter, as β-galactosidase activities of the non-flagellate derivative strain were found to be similar to those of the parental strain after artificially changing the sodium membrane bioenergetics. Similarly, several environmental conditions known to reduce toxin expression were equally effective in reducing :: expression in the motile or non-motile strains. In conclusion, the flagellum of does not act as a mechanosensor, voltmeter or signal transducer for environmental conditions. Thus, alternative mechanisms for the detection of these conditions must exist that likely do not involve the ToxR molecule, as the sensing of all of the tested parameters occurred when the TcpP/H proteins alone activated the :: reporter gene.

  • Received:
  • Accepted:
  • Revised:
  • Published Online:
Keyword(s): CCCP, carbonyl cyanide m-chlorophenylhydrazone , cholera , CT, cholera toxin , mechanosensitive ion channels , motility , MS, mechanosensitive , PVP, polyvinylpyrrolidone , s.m.f., sodium motive force , sodium bioenergetics and TCP, toxin-coregulated pili
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2001-04-01
2024-04-19
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References

  1. Berrier C., Coulombe A., Szabo I., Zoratti M., Ghazi A. 1992; Gadolinium ion inhibits loss of metabolites induced by osmotic shock and large stretch-activated channels in bacteria. Eur J Biochem 206:559–565 [CrossRef]
     [Google Scholar]
  2. Berrier C., Besnard M., Ajouz B., Coulombe A., Ghazi A. 1996; Multiple mechanosensitive ion channels from Escherichia coli , activated at different thresholds of applied pressure. J Membr Biol 151:175–187 [CrossRef]
     [Google Scholar]
  3. Dibrov P. 2000; Lowering the electric potential on the membrane as a possible signal modulating the expression of virulence factors in Vibrio cholerae . Mol Microbiol 35:473–475 [CrossRef]
     [Google Scholar]
  4. DiRita V. J. 1995; Three-component regulatory system controlling virulence in Vibrio cholerae . In Two-Component Signal Transduction pp 351–365 Edited by Hoch J. A., Silhavy T. J. Washington, DC: American Society for Microbiology;
     [Google Scholar]
  5. DiRita V. J., Parsot C., Jander G., Mekalanos J. J. 1991; Regulatory cascade controls virulence in Vibrio cholerae . Proc Natl Acad Sci USA 88:5403–5407 [CrossRef]
     [Google Scholar]
  6. Donnenberg M. S., Kaper J. B. 1991; Construction of an eae deletion mutant of enteropathogenic Escherichia coli by using a positive-selection suicide vector. Infect Immun 59:4310–4317
     [Google Scholar]
  7. Everiss K. D., Hughes K. J., Kovach M. E., Peterson K. M. 1994; The Vibrio cholerae acfB colonization determinant encodes an inner membrane protein that is related to a family of signal-transducing proteins. Infect Immun 62:3289–3298
     [Google Scholar]
  8. Gardel C., Mekalanos J. J. 1996; Alterations in Vibrio cholerae motility phenotypes correlate with changes in virulence factor expression. Infect Immun 64:2246–2255
     [Google Scholar]
  9. Gosink K. K., Häse C. C. 2000; Requirements for the conversion of the Na+-driven flagellar motor of Vibrio cholerae to the H+-driven motor of Escherichia coli . J Bacteriol 182:4234–4240 [CrossRef]
     [Google Scholar]
  10. Gupta S., Chowdhury R. 1997; Bile affects production of virulence factors and motility of Vibrio cholerae . Infect Immun 65:1131–1134
     [Google Scholar]
  11. Harkey C. W., Everiss K. D., Peterson K. M. 1994; The Vibrio cholerae toxin-coregulated-pilus gene tcpI encodes a homolog of methyl-accepting chemotaxis proteins. Infect Immun 62:2669–2678
     [Google Scholar]
  12. Häse C. C. Mekalanos J. J. 1998; TcpP protein is a positive regulator of virulence gene expression in Vibrio cholerae . Proc Natl Acad Sci USA 95:730–734 [CrossRef]
     [Google Scholar]
  13. Häse C. C. Mekalanos J. J. 1999; Effects of changes in membrane sodium flux on virulence gene expression in Vibrio cholerae . Proc Natl Acad Sci USA 96:3183–3187 [CrossRef]
     [Google Scholar]
  14. Häse C. C. LeDain A. C., Martinac B. 1997; Molecular dissection of the large mechanosensitive ion channel (MscL) of E. coli mutants with altered channel gating and pressure sensitivity. J Membr Biol 157:17–25 [CrossRef]
     [Google Scholar]
  15. Holmgren J., Svennerholm A. M. 1973; Enzyme-linked immunosorbent assays for cholera serology. Infect Immun 7:759–763
     [Google Scholar]
  16. Kawagishi I., Imagawa M., Imae Y., McCarter L., Homma M. 1996; The sodium-driven polar flagellar motor of marine Vibrio as the mechanosensor that regulates lateral flagellar gene expression. Mol Microbiol 20:693–699 [CrossRef]
     [Google Scholar]
  17. Kiiyukia C., Kawakami H., Hashimoto H. 1993; Effect of sodium chloride, pH and organic nutrients on the motility of Vibrio cholerae non-01. Microbios 73:249–255
     [Google Scholar]
  18. Klose K. E., Mekalanos J. J. 1998; Differential regulation of multiple flagellins in Vibrio cholerae . J Bacteriol 180:303–316
     [Google Scholar]
  19. Kojima S. K. Y., Kawagishi I., Homma M. 1999; The polar flagellar motor of Vibrio cholerae is driven by a Na+ motive force. J Bacteriol 181:1927–1930
     [Google Scholar]
  20. Levina N., Totemeyer S., Stokes N. R., Louis P., Jones M. A., Booth I. R. 1999; Protection of Escherichia coli cells against extreme turgor by activation of MscS and MscL mechanosensitive channels: identification of genes required for MscS activity. EMBO J 18:1730–1737 [CrossRef]
     [Google Scholar]
  21. McCarter L. 1999; The multiple identities of Vibrio parahaemolyticus . J Mol Microbiol Biotechnol 1:51–57
     [Google Scholar]
  22. Martinac B., Buechner M., Delcour A., Adler J., Kung C. 1987; Pressure-sensitive ion channels in Escherichia coli . Proc Natl Acad Sci USA 84:2297–2301 [CrossRef]
     [Google Scholar]
  23. Martinac B., Adler J., Kung C. 1990; Mechanosensitive ion channels of E. coli activated by amphipaths. Nature 348:261–263 [CrossRef]
     [Google Scholar]
  24. Metcalf W. W., Jiang W., Daniels L. L., Kim S. K., Haldimann A., Wanner B. L. 1996; Conditionally replicative and conjugative plasmids carrying lacZ α for cloning, mutagenesis, and allelle replacement in bacteria. Plasmid 35:1–13 [CrossRef]
     [Google Scholar]
  25. Miller J. H. 1972 Experiments in Molecular Genetics Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
     [Google Scholar]
  26. Miller V., Mekalanos J. 1988; A novel suicide vector and its use in construction of insertion mutations: osmoregulation of outer membrane proteins and virulence determinants in Vibrio cholerae requires toxR . J Bacteriol 170:2575–2583
     [Google Scholar]
  27. Ottemann K. M., Miller J. F. 1997; Roles for motility in bacterial–host interactions. Mol Microbiol 24:1109–1117 [CrossRef]
     [Google Scholar]
  28. Pinner E., Padan E., Schuldiner S. 1995; Amiloride and harmaline are potent inhibitors of NhaB, a Na+/H+ antiporter from Escherichia coli . FEBS Lett 365:18–22 [CrossRef]
     [Google Scholar]
  29. Rampersaud A., Inouye M. 1991; Procaine, a local anesthetic, signals through the EnvZ receptor to change the DNA binding affinity of the transcriptional activator protein OmpR. J Bacteriol 173:6882–6888
     [Google Scholar]
  30. Schumacher D., Klose K. 1999; Environmental signals modulate ToxT-dependent virulence factor expression in Vibrio cholerae . J Bacteriol 181:1508–1514
     [Google Scholar]
  31. Skorupski K., Taylor R. K. 1997; Control of the ToxR virulence regulon in Vibrio cholerae by environmental stimuli. Mol Microbiol 25:1003–1009 [CrossRef]
     [Google Scholar]
  32. Sukharev S. I., Blount P., Martinac B., Blattner F. R., Kung C. 1994; A large-conductance mechanosensitive channel in E. coli encoded by mscL alone. Nature 368:265–268 [CrossRef]
     [Google Scholar]
  33. Tanji K., Ohta Y., Kawato S., Mizushima T., Natori S., Sekimizu K. 1992; Decrease of psychotropic drugs and local anaesthetics of membrane fluidity measured by fluorescence anisotropy in Escherichia coli . J Pharm Pharmacol 44:1036–1037
     [Google Scholar]
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Analysis of the role of flagellar activity in virulence gene expression in Vibrio cholerae
Microbiology 147, 831 (2001); https://doi.org/10.1099/00221287-147-4-831
/content/journal/micro/10.1099/00221287-147-4-831
/content/journal/micro/10.1099/00221287-147-4-831
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