PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of iaiPermissionsJournals.ASM.orgJournalIAI ArticleJournal InfoAuthorsReviewers
 
Infect Immun. 1994 September; 62(9): 3604–3607.
PMCID: PMC303008

Effect of gastric pH on urease-dependent colonization of gnotobiotic piglets by Helicobacter pylori.

Abstract

Thirty-seven gnotobiotic piglets from seven litters were infected with either Helicobacter pylori N6 or urease-negative H. pylori N6ureG::Km which contains an insertion in the ureG gene and produces inactive urease. To produce achlorhydria, piglets were treated throughout the experiment with omeprazole (5 mg intravenously every 12 h) and ranitidine (75 mg orally every 6 h). Treatment resulted in elevation of gastric pH to 7.0 +/- 1.1 throughout the experiment. Control piglets were not treated and remained normochlorhydric. Strain N6 colonized well in both normal and achlorhydric piglets. All 10 piglets were colonized, and colonization ranged from 4.4 +/- 1.5 log10 CFU/g of gastric mucosa in normochlorhydric piglets sacrificed after 2 days to 6.9 +/- 0.5 log10 CFU/g in normochlorhydric piglets sacrificed after 5 days. Strain N6ureG::Km did not colonize any of seven normochlorhydric piglets and was recovered only in low numbers (< 100 CFU/g) from four of nine achlorhydric piglets. In the second experiment, piglets were coinoculated with both strains N6 and N6ureG::Km. Coinoculation did not affect colonization by urease-positive N6. Urease-deficient N6ureG::Km was unable to colonize even in the presence of urease-positive bacteria. These results confirm that urease enzymatic activity (and not urease protein) is essential for colonization, that this effect is independent of diffusible products of urea metabolism, and that gastric pH protection is not a major role of urease in promoting colonization by H. pylori.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (786K), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Bode G, Malfertheiner P, Nilius M, Lehnhardt G, Ditschuneit H. Ultrastructural localisation of urease in outer membrane and periplasm of Campylobacter pylori. J Clin Pathol. 1989 Jul;42(7):778–779. [PMC free article] [PubMed]
  • Bronsdon MA, Goodwin CS, Sly LI, Chilvers T, Schoenknecht FD. Helicobacter nemestrinae sp. nov., a spiral bacterium found in the stomach of a pigtailed macaque (Macaca nemestrina) Int J Syst Bacteriol. 1991 Jan;41(1):148–153. [PubMed]
  • Dick JD. Helicobacter (Campylobacter) pylori: a new twist to an old disease. Annu Rev Microbiol. 1990;44:249–269. [PubMed]
  • Eaton KA, Krakowka S. Chronic active gastritis due to Helicobacter pylori in immunized gnotobiotic piglets. Gastroenterology. 1992 Nov;103(5):1580–1586. [PubMed]
  • Eaton KA, Brooks CL, Morgan DR, Krakowka S. Essential role of urease in pathogenesis of gastritis induced by Helicobacter pylori in gnotobiotic piglets. Infect Immun. 1991 Jul;59(7):2470–2475. [PMC free article] [PubMed]
  • Ferrero RL, Cussac V, Courcoux P, Labigne A. Construction of isogenic urease-negative mutants of Helicobacter pylori by allelic exchange. J Bacteriol. 1992 Jul;174(13):4212–4217. [PMC free article] [PubMed]
  • Hawtin PR, Stacey AR, Newell DG. Investigation of the structure and localization of the urease of Helicobacter pylori using monoclonal antibodies. J Gen Microbiol. 1990 Oct;136(10):1995–2000. [PubMed]
  • Hu LT, Mobley HL. Purification and N-terminal analysis of urease from Helicobacter pylori. Infect Immun. 1990 Apr;58(4):992–998. [PMC free article] [PubMed]
  • Krakowka S, Morgan DR, Kraft WG, Leunk RD. Establishment of gastric Campylobacter pylori infection in the neonatal gnotobiotic piglet. Infect Immun. 1987 Nov;55(11):2789–2796. [PMC free article] [PubMed]
  • McNulty CA, Dent JC, Curry A, Uff JS, Ford GA, Gear MW, Wilkinson SP. New spiral bacterium in gastric mucosa. J Clin Pathol. 1989 Jun;42(6):585–591. [PMC free article] [PubMed]
  • Morgan DR, Freedman R, Depew CE, Kraft WG. Growth of Campylobacter pylori in liquid media. J Clin Microbiol. 1987 Nov;25(11):2123–2125. [PMC free article] [PubMed]
  • Paster BJ, Lee A, Fox JG, Dewhirst FE, Tordoff LA, Fraser GJ, O'Rourke JL, Taylor NS, Ferrero R. Phylogeny of Helicobacter felis sp. nov., Helicobacter mustelae, and related bacteria. Int J Syst Bacteriol. 1991 Jan;41(1):31–38. [PubMed]
  • Romano N, Tolone G, Ajello F, La Licata R. Adenosine 5'-triphosphate synthesis induced by urea hydrolysis in Ureaplasma urealyticum. J Bacteriol. 1980 Nov;144(2):830–832. [PMC free article] [PubMed]
  • Rudmann DG, Eaton KA, Krakowka S. Ultrastructural study of Helicobacter pylori adherence properties in gnotobiotic piglets. Infect Immun. 1992 May;60(5):2121–2124. [PMC free article] [PubMed]
  • Solnick JV, O'Rourke J, Lee A, Paster BJ, Dewhirst FE, Tompkins LS. An uncultured gastric spiral organism is a newly identified Helicobacter in humans. J Infect Dis. 1993 Aug;168(2):379–385. [PubMed]

Articles from Infection and Immunity are provided here courtesy of American Society for Microbiology (ASM)