Abstract
Helicobacter pylori is a spiral, gram-negative bacterium which causes chronic gastritis and plays a critical role in peptic ulcer disease, gastric carcinoma, and gastric lymphoma. H. pylori expresses significant urease activity which is an essential virulence factor. Since a significant fraction of urease activity is located on the surface of the bacterium, the urease molecule is a logical choice as an antigen for a vaccine; currently recombinant urease apoenzyme is being tested as a vaccine in phase II clinical trials. We have recently demonstrated that urease and HspB (a homolog of the GroEL heat shock protein) become associated with the surface of H. pylori in vitro in a novel manner: these cytoplasmic proteins are released by bacterial autolysis and become adsorbed to the surface of intact bacteria, reflecting the unique characteristics of the outer membrane. To determine if similar mechanisms are operative in vivo, we determined the ultrastructural locations of urease and HspB within bacteria present in human gastric biopsies. Our results demonstrate that both urease and HspB are located within the cytoplasm of all bacteria examined in human gastric biopsies. Interestingly, a significant proportion of the bacteria examined also possessed variable amounts of surface-associated urease and HspB antigen (from 5 to 50% of the total antigenic material), indicating that in vivo, H. pylori has surface characteristics which enable it to adsorb cytoplasmic proteins. This is consistent with our altruistic autolysis model in which H. pylori uses genetically programmed bacterial autolysis to release urease and other cytoplasmic proteins which are subsequently adsorbed onto the surface of neighboring viable bacteria. These observations have important implications regarding pathogenesis and development of vaccines for H. pylori.
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- Berry A. M., Paton J. C., Hansman D. Effect of insertional inactivation of the genes encoding pneumolysin and autolysin on the virulence of Streptococcus pneumoniae type 3. Microb Pathog. 1992 Feb;12(2):87–93. doi: 10.1016/0882-4010(92)90111-z. [DOI] [PubMed] [Google Scholar]
- Blaser M. J. Hypotheses on the pathogenesis and natural history of Helicobacter pylori-induced inflammation. Gastroenterology. 1992 Feb;102(2):720–727. doi: 10.1016/0016-5085(92)90126-j. [DOI] [PubMed] [Google Scholar]
- Clayton C. L., Pallen M. J., Kleanthous H., Wren B. W., Tabaqchali S. Nucleotide sequence of two genes from Helicobacter pylori encoding for urease subunits. Nucleic Acids Res. 1990 Jan 25;18(2):362–362. doi: 10.1093/nar/18.2.362. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Corthésy-Theulaz I., Porta N., Glauser M., Saraga E., Vaney A. C., Haas R., Kraehenbuhl J. P., Blum A. L., Michetti P. Oral immunization with Helicobacter pylori urease B subunit as a treatment against Helicobacter infection in mice. Gastroenterology. 1995 Jul;109(1):115–121. doi: 10.1016/0016-5085(95)90275-9. [DOI] [PubMed] [Google Scholar]
- Cussac V., Ferrero R. L., Labigne A. Expression of Helicobacter pylori urease genes in Escherichia coli grown under nitrogen-limiting conditions. J Bacteriol. 1992 Apr;174(8):2466–2473. doi: 10.1128/jb.174.8.2466-2473.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dent J. C., McNulty C. A. Evaluation of a new selective medium for Campylobacter pylori. Eur J Clin Microbiol Infect Dis. 1988 Aug;7(4):555–558. doi: 10.1007/BF01962615. [DOI] [PubMed] [Google Scholar]
- Dunn B. E., Campbell G. P., Perez-Perez G. I., Blaser M. J. Purification and characterization of urease from Helicobacter pylori. J Biol Chem. 1990 Jun 5;265(16):9464–9469. [PubMed] [Google Scholar]
- Dunn B. E., Sung C. C., Taylor N. S., Fox J. G. Purification and characterization of Helicobacter mustelae urease. Infect Immun. 1991 Sep;59(9):3343–3345. doi: 10.1128/iai.59.9.3343-3345.1991. [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]
- Fath M. J., Kolter R. ABC transporters: bacterial exporters. Microbiol Rev. 1993 Dec;57(4):995–1017. doi: 10.1128/mr.57.4.995-1017.1993. [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]
- Ferrero R. L., Thiberge J. M., Huerre M., Labigne A. Recombinant antigens prepared from the urease subunits of Helicobacter spp.: evidence of protection in a mouse model of gastric infection. Infect Immun. 1994 Nov;62(11):4981–4989. doi: 10.1128/iai.62.11.4981-4989.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- García J. L., Sánchez-Puelles J. M., García P., López R., Ronda C., García E. Molecular characterization of an autolysin-defective mutant of Streptococcus pneumoniae. Biochem Biophys Res Commun. 1986 Jun 13;137(2):614–619. doi: 10.1016/0006-291x(86)91122-8. [DOI] [PubMed] [Google Scholar]
- Hu L. T., Mobley H. L. Purification and N-terminal analysis of urease from Helicobacter pylori. Infect Immun. 1990 Apr;58(4):992–998. doi: 10.1128/iai.58.4.992-998.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jarvis K. G., Girón J. A., Jerse A. E., McDaniel T. K., Donnenberg M. S., Kaper J. B. Enteropathogenic Escherichia coli contains a putative type III secretion system necessary for the export of proteins involved in attaching and effacing lesion formation. Proc Natl Acad Sci U S A. 1995 Aug 15;92(17):7996–8000. doi: 10.1073/pnas.92.17.7996. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jonsson A. B., Nyberg G., Normark S. Phase variation of gonococcal pili by frameshift mutation in pilC, a novel gene for pilus assembly. EMBO J. 1991 Feb;10(2):477–488. doi: 10.1002/j.1460-2075.1991.tb07970.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lee C. K., Weltzin R., Thomas W. D., Jr, Kleanthous H., Ermak T. H., Soman G., Hill J. E., Ackerman S. K., Monath T. P. Oral immunization with recombinant Helicobacter pylori urease induces secretory IgA antibodies and protects mice from challenge with Helicobacter felis. J Infect Dis. 1995 Jul;172(1):161–172. doi: 10.1093/infdis/172.1.161. [DOI] [PubMed] [Google Scholar]
- Marshall B. J., Barrett L. J., Prakash C., McCallum R. W., Guerrant R. L. Urea protects Helicobacter (Campylobacter) pylori from the bactericidal effect of acid. Gastroenterology. 1990 Sep;99(3):697–702. doi: 10.1016/0016-5085(90)90957-3. [DOI] [PubMed] [Google Scholar]
- Michetti P., Corthésy-Theulaz I., Davin C., Haas R., Vaney A. C., Heitz M., Bille J., Kraehenbuhl J. P., Saraga E., Blum A. L. Immunization of BALB/c mice against Helicobacter felis infection with Helicobacter pylori urease. Gastroenterology. 1994 Oct;107(4):1002–1011. doi: 10.1016/0016-5085(94)90224-0. [DOI] [PubMed] [Google Scholar]
- Mobley H. L., Island M. D., Hausinger R. P. Molecular biology of microbial ureases. Microbiol Rev. 1995 Sep;59(3):451–480. doi: 10.1128/mr.59.3.451-480.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pappo J., Thomas W. D., Jr, Kabok Z., Taylor N. S., Murphy J. C., Fox J. G. Effect of oral immunization with recombinant urease on murine Helicobacter felis gastritis. Infect Immun. 1995 Apr;63(4):1246–1252. doi: 10.1128/iai.63.4.1246-1252.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parsonnet J., Hansen S., Rodriguez L., Gelb A. B., Warnke R. A., Jellum E., Orentreich N., Vogelman J. H., Friedman G. D. Helicobacter pylori infection and gastric lymphoma. N Engl J Med. 1994 May 5;330(18):1267–1271. doi: 10.1056/NEJM199405053301803. [DOI] [PubMed] [Google Scholar]
- Paton J. C., Andrew P. W., Boulnois G. J., Mitchell T. J. Molecular analysis of the pathogenicity of Streptococcus pneumoniae: the role of pneumococcal proteins. Annu Rev Microbiol. 1993;47:89–115. doi: 10.1146/annurev.mi.47.100193.000513. [DOI] [PubMed] [Google Scholar]
- Peura D. A., Graham D. Y. Helicobacter pylori: consensus reached: peptic ulcer is on the way to becoming an historic disease. Am J Gastroenterol. 1994 Aug;89(8):1137–1139. [PubMed] [Google Scholar]
- Phadnis S. H., Parlow M. H., Levy M., Ilver D., Caulkins C. M., Connors J. B., Dunn B. E. Surface localization of Helicobacter pylori urease and a heat shock protein homolog requires bacterial autolysis. Infect Immun. 1996 Mar;64(3):905–912. doi: 10.1128/iai.64.3.905-912.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pugsley A. P. The complete general secretory pathway in gram-negative bacteria. Microbiol Rev. 1993 Mar;57(1):50–108. doi: 10.1128/mr.57.1.50-108.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Renthal R., Schneider B. G., Miller M. M., Ludueña R. F. Beta IV is the major beta-tubulin isotype in bovine cilia. Cell Motil Cytoskeleton. 1993;25(1):19–29. doi: 10.1002/cm.970250104. [DOI] [PubMed] [Google Scholar]
- Schneider B. G., Papermaster D. S. Immunocytochemistry of retinal membrane protein biosynthesis at the electron microscopic level by the albumin embedding technique. Methods Enzymol. 1983;96:485–495. doi: 10.1016/s0076-6879(83)96042-1. [DOI] [PubMed] [Google Scholar]
- Seifert H. S., Ajioka R. S., Marchal C., Sparling P. F., So M. DNA transformation leads to pilin antigenic variation in Neisseria gonorrhoeae. Nature. 1988 Nov 24;336(6197):392–395. doi: 10.1038/336392a0. [DOI] [PubMed] [Google Scholar]
- Williams C. L., Preston T., Hossack M., Slater C., McColl K. E. Helicobacter pylori utilises urea for amino acid synthesis. FEMS Immunol Med Microbiol. 1996 Jan;13(1):87–94. doi: 10.1111/j.1574-695X.1996.tb00220.x. [DOI] [PubMed] [Google Scholar]