Abstract
The aim of this work was to study the significance of the urease enzyme in promoting Helicobacter pylori survival in various environments. A urease-positive H. pylori isolate, strain N6, and an isogenic urease-negative strain, strain N6(ureB::TnKm), were incubated in phosphate-buffered saline at a pH ranging from 2.2 to 7.2 for 60 min at 37 degrees C in both the presence and the absence of 10 mM urea. The number of CFU per milliliter in each solution, the pH of the bacterial supernatant, and the amounts of ammonia present in the solutions were measured. H. pylori N6 survived well in solutions with pH values ranging from 4.5 to 7.0 in the absence of urea but survived in solutions only with an initial pH below 3.5 in the presence of urea. Neither strain grew after incubation in an alkaline environment. The pH of an acidic solution (i.e., 3.5) rose rapidly to 8.45 in the presence of the wild-type strain and urea. The urease-negative mutant survived in solutions with pH values ranging from 4.5 to 7.2 irrespective of the presence of urea. Ammonia was present in significant amounts when H. pylori N6 was incubated in the presence of urea. Strain N6 survived exposure to concentrations of ammonia as high as 80 mM. The acid environment of the stomach may be crucial for H. pylori survival in the presence of urea. H. pylori does not survive in the normal environment in the presence of urea because of the subsequent rise in pH rather than ammonia toxicity.
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- Cave D. R., Vargas M. Effect of a Campylobacter pylori protein on acid secretion by parietal cells. Lancet. 1989 Jul 22;2(8656):187–189. doi: 10.1016/s0140-6736(89)90372-3. [DOI] [PubMed] [Google Scholar]
- Clyne M., Drumm B. Adherence of Helicobacter pylori to primary human gastrointestinal cells. Infect Immun. 1993 Oct;61(10):4051–4057. doi: 10.1128/iai.61.10.4051-4057.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Crabtree J. E., Figura N., Taylor J. D., Bugnoli M., Armellini D., Tompkins D. S. Expression of 120 kilodalton protein and cytotoxicity in Helicobacter pylori. J Clin Pathol. 1992 Aug;45(8):733–734. doi: 10.1136/jcp.45.8.733. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Drumm B., Sherman P. Long-term storage of Campylobacter pylori. J Clin Microbiol. 1989 Jul;27(7):1655–1656. doi: 10.1128/jcm.27.7.1655-1656.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eaton K. A., Brooks C. L., Morgan D. R., 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. doi: 10.1128/iai.59.7.2470-2475.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eaton K. A., Krakowka S. Effect of gastric pH on urease-dependent colonization of gnotobiotic piglets by Helicobacter pylori. Infect Immun. 1994 Sep;62(9):3604–3607. doi: 10.1128/iai.62.9.3604-3607.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Falk P., Roth K. A., Borén T., Westblom T. U., Gordon J. I., Normark S. An in vitro adherence assay reveals that Helicobacter pylori exhibits cell lineage-specific tropism in the human gastric epithelium. Proc Natl Acad Sci U S A. 1993 Mar 1;90(5):2035–2039. doi: 10.1073/pnas.90.5.2035. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ferrero R. L., 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. doi: 10.1128/jb.174.13.4212-4217.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Figura N., Guglielmetti P., Rossolini A., Barberi A., Cusi G., Musmanno R. A., Russi M., Quaranta S. Cytotoxin production by Campylobacter pylori strains isolated from patients with peptic ulcers and from patients with chronic gastritis only. J Clin Microbiol. 1989 Jan;27(1):225–226. doi: 10.1128/jcm.27.1.225-226.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Flejou J. F., Bahame P., Smith A. C., Stockbrugger R. W., Rode J., Price A. B. Pernicious anaemia and Campylobacter like organisms; is the gastric antrum resistant to colonisation? Gut. 1989 Jan;30(1):60–64. doi: 10.1136/gut.30.1.60. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Graham D. Y. Treatment of peptic ulcers caused by Helicobacter pylori. N Engl J Med. 1993 Feb 4;328(5):349–350. doi: 10.1056/NEJM199302043280512. [DOI] [PubMed] [Google Scholar]
- Hammar M., Tyszkiewicz T., Wadström T., O'Toole P. W. Rapid detection of Helicobacter pylori in gastric biopsy material by polymerase chain reaction. J Clin Microbiol. 1992 Jan;30(1):54–58. doi: 10.1128/jcm.30.1.54-58.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hazell S. L., Evans D. J., Jr, Graham D. Y. Helicobacter pylori catalase. J Gen Microbiol. 1991 Jan;137(1):57–61. doi: 10.1099/00221287-137-1-57. [DOI] [PubMed] [Google Scholar]
- Hazell S. L., Lee A., Brady L., Hennessy W. Campylobacter pyloridis and gastritis: association with intercellular spaces and adaptation to an environment of mucus as important factors in colonization of the gastric epithelium. J Infect Dis. 1986 Apr;153(4):658–663. doi: 10.1093/infdis/153.4.658. [DOI] [PubMed] [Google Scholar]
- Hentschel E., Brandstätter G., Dragosics B., Hirschl A. M., Nemec H., Schütze K., Taufer M., Wurzer H. Effect of ranitidine and amoxicillin plus metronidazole on the eradication of Helicobacter pylori and the recurrence of duodenal ulcer. N Engl J Med. 1993 Feb 4;328(5):308–312. doi: 10.1056/NEJM199302043280503. [DOI] [PubMed] [Google Scholar]
- Kelly S. M., Crampton J. R., Hunter J. O. Helicobacter pylori increases gastric antral juxtamucosal pH. Dig Dis Sci. 1993 Jan;38(1):129–131. doi: 10.1007/BF01296784. [DOI] [PubMed] [Google Scholar]
- Kim H., Park C., Jang W. I., Lee K. H., Kwon S. O., Robey-Cafferty S. S., Ro J. Y., Lee Y. B. The gastric juice urea and ammonia levels in patients with Campylobacter pylori. Am J Clin Pathol. 1990 Aug;94(2):187–191. doi: 10.1093/ajcp/94.2.187. [DOI] [PubMed] [Google Scholar]
- Krajden S., Fuksa M., Anderson J., Kempston J., Boccia A., Petrea C., Babida C., Karmali M., Penner J. L. Examination of human stomach biopsies, saliva, and dental plaque for Campylobacter pylori. J Clin Microbiol. 1989 Jun;27(6):1397–1398. doi: 10.1128/jcm.27.6.1397-1398.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Leunk R. D., Johnson P. T., David B. C., Kraft W. G., Morgan D. R. Cytotoxic activity in broth-culture filtrates of Campylobacter pylori. J Med Microbiol. 1988 Jun;26(2):93–99. doi: 10.1099/00222615-26-2-93. [DOI] [PubMed] [Google Scholar]
- Marshall B. J., Goodwin C. S., Warren J. R., Murray R., Blincow E. D., Blackbourn S. J., Phillips M., Waters T. E., Sanderson C. R. Prospective double-blind trial of duodenal ulcer relapse after eradication of Campylobacter pylori. Lancet. 1988 Dec 24;2(8626-8627):1437–1442. doi: 10.1016/s0140-6736(88)90929-4. [DOI] [PubMed] [Google Scholar]
- Mitchell H. M., Li Y. Y., Hu P. J., Liu Q., Chen M., Du G. G., Wang Z. J., Lee A., Hazell S. L. Epidemiology of Helicobacter pylori in southern China: identification of early childhood as the critical period for acquisition. J Infect Dis. 1992 Jul;166(1):149–153. doi: 10.1093/infdis/166.1.149. [DOI] [PubMed] [Google Scholar]
- Mobley H. L., Cortesia M. J., Rosenthal L. E., Jones B. D. Characterization of urease from Campylobacter pylori. J Clin Microbiol. 1988 May;26(5):831–836. doi: 10.1128/jcm.26.5.831-836.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morris A., Nicholson G. Ingestion of Campylobacter pyloridis causes gastritis and raised fasting gastric pH. Am J Gastroenterol. 1987 Mar;82(3):192–199. [PubMed] [Google Scholar]
- Nagata K., Satoh H., Iwahi T., Shimoyama T., Tamura T. Potent inhibitory action of the gastric proton pump inhibitor lansoprazole against urease activity of Helicobacter pylori: unique action selective for H. pylori cells. Antimicrob Agents Chemother. 1993 Apr;37(4):769–774. doi: 10.1128/aac.37.4.769. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nguyen A. M., Engstrand L., Genta R. M., Graham D. Y., el-Zaatari F. A. Detection of Helicobacter pylori in dental plaque by reverse transcription-polymerase chain reaction. J Clin Microbiol. 1993 Apr;31(4):783–787. doi: 10.1128/jcm.31.4.783-787.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- O'Connor H. J., Axon A. T., Dixon M. F. Campylobacter-like organisms unusual in type A (pernicious anaemia) gastritis. Lancet. 1984 Nov 10;2(8411):1091–1091. doi: 10.1016/s0140-6736(84)91523-x. [DOI] [PubMed] [Google Scholar]
- O'Connor H. J., Newbold K. M., Alexander-Williams J., Thompson H., Drumm J., Donovan I. A. Effect of Roux-en-Y biliary diversion on Campylobacter pylori. Gastroenterology. 1989 Oct;97(4):958–964. doi: 10.1016/0016-5085(89)91504-7. [DOI] [PubMed] [Google Scholar]
- O'Connor H. J., Wyatt J. I., Dixon M. F., Axon A. T. Campylobacter like organisms and reflux gastritis. J Clin Pathol. 1986 May;39(5):531–534. doi: 10.1136/jcp.39.5.531. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Offerhaus G. J., Rieu P. N., Jansen J. B., Joosten H. J., Lamers C. B. Prospective comparative study of the influence of postoperative bile reflux on gastric mucosal histology and Campylobacter pylori infection. Gut. 1989 Nov;30(11):1552–1557. doi: 10.1136/gut.30.11.1552. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peterson W. L. Helicobacter pylori and peptic ulcer disease. N Engl J Med. 1991 Apr 11;324(15):1043–1048. doi: 10.1056/NEJM199104113241507. [DOI] [PubMed] [Google Scholar]
- Pérez-Pérez G. I., Olivares A. Z., Cover T. L., Blaser M. J. Characteristics of Helicobacter pylori variants selected for urease deficiency. Infect Immun. 1992 Sep;60(9):3658–3663. doi: 10.1128/iai.60.9.3658-3663.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Segal E. D., Shon J., Tompkins L. S. Characterization of Helicobacter pylori urease mutants. Infect Immun. 1992 May;60(5):1883–1889. doi: 10.1128/iai.60.5.1883-1889.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Slomiany B. L., Bilski J., Sarosiek J., Murty V. L., Dworkin B., VanHorn K., Zielenski J., Slomiany A. Campylobacter pyloridis degrades mucin and undermines gastric mucosal integrity. Biochem Biophys Res Commun. 1987 Apr 14;144(1):307–314. doi: 10.1016/s0006-291x(87)80511-9. [DOI] [PubMed] [Google Scholar]
- Slomiany B. L., Nishikawa H., Piotrowski J., Okazaki K., Slomiany A. Lipolytic activity of Campylobacter pylori: effect of sofalcone. Digestion. 1989;43(1-2):33–40. doi: 10.1159/000199858. [DOI] [PubMed] [Google Scholar]
- Spiegelhalder C., Gerstenecker B., Kersten A., Schiltz E., Kist M. Purification of Helicobacter pylori superoxide dismutase and cloning and sequencing of the gene. Infect Immun. 1993 Dec;61(12):5315–5325. doi: 10.1128/iai.61.12.5315-5325.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stanley J., Linton D., Burnens A. P., Dewhirst F. E., Owen R. J., Porter A., On S. L., Costas M. Helicobacter canis sp. nov., a new species from dogs: an integrated study of phenotype and genotype. J Gen Microbiol. 1993 Oct;139(10):2495–2504. doi: 10.1099/00221287-139-10-2495. [DOI] [PubMed] [Google Scholar]
- Stolte M., Bethke B. Elimination of Helicobacter pylori under treatment with omeprazole. Z Gastroenterol. 1990 Jun;28(6):271–274. [PubMed] [Google Scholar]
- Thomas J. E., Gibson G. R., Darboe M. K., Dale A., Weaver L. T. Isolation of Helicobacter pylori from human faeces. Lancet. 1992 Nov 14;340(8829):1194–1195. doi: 10.1016/0140-6736(92)92894-l. [DOI] [PubMed] [Google Scholar]
- Wyatt J. I., Rathbone B. J., Dixon M. F., Heatley R. V. Campylobacter pyloridis and acid induced gastric metaplasia in the pathogenesis of duodenitis. J Clin Pathol. 1987 Aug;40(8):841–848. doi: 10.1136/jcp.40.8.841. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van Zwet A. A., Thijs J. C., Kooistra-Smid A. M., Schirm J., Snijder J. A. Use of PCR with feces for detection of Helicobacter pylori infections in patients. J Clin Microbiol. 1994 May;32(5):1346–1348. doi: 10.1128/jcm.32.5.1346-1348.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]