1887

Abstract

is an aetiological agent of gastric disease. Although the role of urease in gastric colonization of has been shown, it remains unclear as to where urease is located in this bacterial cell. The purpose of this study was to define the urease-associated apparatus in the cytoplasm. was incubated at both a neutral and an acidic pH in the presence or absence of urea and examined by double indirect immunoelectron microscopy. The density of gold particles for UreA was greatest in the inner portion of the wild-type cytoplasm at neutral pH but was greatest in the outer portion at acidic pH. This difference was independent of the presence of urea and was not observed in the -deletion mutant. Also, the eccentric shift of urease in acidic pH was not observed in UreI. After a 2 day incubation period at acidic pH, it was observed that the urease gold particles in assembled and were associated with UreI gold particles. Urease immunoreactivity shifted from the inner to the outer portion of as a result of an extracellular decrease in pH. This shift was urea-independent and UreI-dependent, suggesting an additional role of UreI in urease-dependent acid resistance. This is the first report of the intracellular transport of molecules in bacteria in response to changes in the extracellular environment.

Loading

Article metrics loading...

/content/journal/jmm/10.1099/jmm.0.05072-0
2003-03-01
2024-05-04
Loading full text...

Full text loading...

/deliver/fulltext/jmm/52/3/211.html?itemId=/content/journal/jmm/10.1099/jmm.0.05072-0&mimeType=html&fmt=ahah

References

  1. Athmann C, Zeng N, Kang T, Marcus E. A, Scott D. R, Rektorschek M, Buhmann A, Melchers K, Sachs G. 2000; Local pH elevation mediated by the intrabacterial urease of Helicobacter pylori cocultured with gastric cells. J Clin Invest 106:339–347 [CrossRef]
    [Google Scholar]
  2. Bode G, Malfertheiner P, Lehnhardt G, Nilius M, Ditschuneit H. 1993; Ultrastructural localization of urease of Helicobacter pylori . Med Microbiol Immunol (Berl) 182:233–242 [CrossRef]
    [Google Scholar]
  3. Bohnen J. M, Krajden S, Anderson J. G, Kempston J. D, Fuksa M, Karmali M. A, Osborne A, Babida C. 1986; Campylobacter pyloridis is associated with acid-peptic disease in Toronto. Can J Surg 29:442–444
    [Google Scholar]
  4. Dunn B. E, Phadnis S. H. 1998; Structure, function and localization of Helicobacter pylori urease. Yale J Biol Med 71:63–73
    [Google Scholar]
  5. Ha N. C, Oh S. T, Sung J. Y, Cha K. A, Lee M. H, Oh B. H. 2001; Supramolecular assembly and acid resistance of Helicobacter pylori urease. Nat Struct Biol 8:505–509 [CrossRef]
    [Google Scholar]
  6. Hong W, Morimatsu S, Goto T. 8 other authors 2000; Contrast-enhanced immunoelectron microscopy for Helicobacter pylori . J Microbiol Methods 42:121–127 [CrossRef]
    [Google Scholar]
  7. Kurosawa M, Kikuchi S, Inaba Y, Ishibashi T, Kobayashi F. 2000; Helicobacter pylori infection among Japanese children. J Gastroenterol Hepatol 15:1382–1385
    [Google Scholar]
  8. Marcus E. A, Scott D. R. 2001; Cell lysis is responsible for the appearance of extracellular urease in Helicobacter pylori . Helicobacter 6:93–99 [CrossRef]
    [Google Scholar]
  9. McGowan C. C, Cover T. L, Blaser M. J. 1996; Helicobacter pylori and gastric acid: biological and therapeutic implications. Gastroenterology 110:926–938 [CrossRef]
    [Google Scholar]
  10. Meyer-Rosberg K, Scott D. R, Rex D, Melchers K, Sachs G. 1996; The effect of environmental pH on the proton motive force of Helicobacter pylori. Gastroenterology 111:886–900
    [Google Scholar]
  11. Mollenhauer-Rektorschek M, Hanauer G, Sachs G, Melchers K. 2003; Expression of the acid-activated UreI urea channel is required for both infection and colonization by Helicobacter pylori in gerbil stomach. Res Microbiol in press
    [Google Scholar]
  12. Nilius M, Bode G, Lehnhardt G, Malfertheiner P. 1991; In vitro inhibition of Helicobacter pylori urease: biochemical and ultrastructural analysis. Eur J Clin Invest 21:551–557 [CrossRef]
    [Google Scholar]
  13. Rain J. C, Selig L, De Reuse H. 10 other authors 2001; The protein–protein interaction map of Helicobacter pylori . Nature 409:211–215 [CrossRef]
    [Google Scholar]
  14. Rektorschek M, Weeks D, Sachs G, Melchers K. 1998; Influence of pH on metabolism and urease activity of Helicobacter pylori . Gastroenterology 115:628–641 [CrossRef]
    [Google Scholar]
  15. Scott D. R, Marcus E. A, Weeks D. L, Lee A, Melchers K, Sachs G. 2000; Expression of the Helicobacter pylori ureI gene is required for acidic pH activation of cytoplasmic urease. Infect Immun 68:470–477 [CrossRef]
    [Google Scholar]
  16. Scott D. R, Weeks D, Hong C, Postius S, Melchers K, Sachs G. 1998; The role of internal urease in acid resistance of Helicobacter pylori . Gastroenterology 114:58–70 [CrossRef]
    [Google Scholar]
  17. Skouloubris S, Thiberge J. M, Labigne A, De Reuse H. 1998; The Helicobacter pylori UreI protein is not involved in urease activity but is essential for bacterial survival in vivo . Infect Immun 66:4517–4521
    [Google Scholar]
  18. Voland P, Marcus E. A, Weeks D. L, Prinz C, Sachs G, Scott D. R. 2003; Interactions of the seven Helicobacter pylori proteins encoded by the urease gene cluster. Am J Physiol (in press
    [Google Scholar]
  19. Wadström T. 1995; An update on Helicobacter pylori . Curr Opin Gastroenterol 11:69–75 [CrossRef]
    [Google Scholar]
  20. Warren J. R, Marshall B. 1983; Unidentified curved bacilli on gastric epithelium in active chronic gastritis. Lancet i:1273–1275
    [Google Scholar]
  21. Weeks D. L, Sachs G. 2001; Sites of pH regulation of the urea channel of Helicobacter pylori . Mol Microbiol 40:1249–1259 [CrossRef]
    [Google Scholar]
  22. Weeks D. L, Eskandari S, Scott D. R, Sachs G. 2000; A H+-gated urea channel: the link between Helicobacter pylori urease and gastric colonization. Science 287:482–485 [CrossRef]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jmm/10.1099/jmm.0.05072-0
Loading
/content/journal/jmm/10.1099/jmm.0.05072-0
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error