The urea cycle of Helicobacter pylori
Abstract
The presence and activities of the enzymes of the urea cycle in the bacterium Helicobacter pylori were investigated employing one- and two-dimensional NMR spectroscopy and radioactive tracer analysis. Cell suspensions, lysates and membrane preparations generated L-ornithine and ammonium at high rates in incubations with L-arginine, indicating the presence of arginase activity. Anabolic ornithine transcarbamoylase (OTCase) activity was identified by the formation of heat-stable products in incubations of cell-free extracts with ornithine and radiolabelled carbamoyl phosphate. The heat-labile product that resulted from incubations of cell-free extracts with citrulline radiolabelled in the guanidino moiety revealed the presence of catabolic OTCase activity. Argininosuccinate formation and catalysis indicated the presence of argininosuccinate synthetase and argininosuccinase activities. The findings suggested that H. pylori has a urea cycle which acts as an effective mechanism to extrude excess nitrogen from cells.
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Several recent studies have reported arginase activity in S. clavuligerus.
“Even though presence of the urea cycle in prokaryotes was once considered unusual, several recent studies have reported arginase activity in S. clavuligerus (Mendz and Hazell, 1996; Bushell et al., 2006).”
From Fermentation Conditions that Affect Clavulanic Acid Production in Streptomyces clavuligerus: A Systematic Review (2016) · cites this paper as Mendz and Hazell, 1996
Cites
Effect of gastric pH on urease-dependent colonization of gnotobiotic piglets by Helicobacter pylori
Eaton, K. A., & Krakowka, S. (1994) · Infection and Immunity · doi:10.1128/iai.62.9.3604-3607.1994 · Cited by 330 · see citing works
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Pathogenesis of <i>Helicobacter pylori</i> Infection
Kusters, J. G., van Vliet, A. H. M., & Kuipers, E. J. (2006) · Clinical Microbiology Reviews · doi:10.1128/cmr.00054-05 · Cited by 2,526 · see citing works
Ser, H.-L., Law, J. W.-F., Chaiyakunapruk, N., Jacob, S. A., Palanisamy, U. D., Chan, K.-G., Goh, B.-H., & Lee, L.-H. (2016) · Frontiers in Microbiology · doi:10.3389/fmicb.2016.00522 · Cited by 90 · see citing works
“Even though presence of the urea cycle in prokaryotes was once considered unusual, several recent studies have reported arginase activity in S. clavuligerus (Mendz and Hazell, 1996; Bushell et al., 2006).”
BackgroundMcGee, D. J., Zabaleta, J., Viator, R. J., Testerman, T. L., Ochoa, A. C., & Mendz, G. L. (2004) · European Journal of Biochemistry · doi:10.1111/j.1432-1033.2004.04105.x · Cited by 84 · see citing works
Self-citation
- Authors
- Mendz, G. L., & Hazell, S. L.
- Affiliations
- UNSW Sydney (AU)
- Corresponding author
- Mendz, G. L.
- ORCID
- Mendz, G. L.
- Venue
- Microbiology
- Publisher
- Microbiology Society
- Published
- 1996-10-01
- Volume
- 142
- Issue
- 10
- Pages
- 2959-2967
- ISSN
- 1350-0872 (ISSN-L)
- 1465-2080
- OpenAlex
- W1983151151
- Cited by
- 83
- References
- 1
- Citations by year
- 2026: 1 · 2025: 1 · 2024: 2 · 2023: 2 · 2022: 2 · 2021: 2 · 2020: 3 · 2019: 1 · 2018: 9 · 2017: 3 · 2016: 1 · 2014: 7 · 2012: 1
- FWCI
- 2.84
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Microbiology (publishedVersion)
- PubMed (publishedVersion)
- Funders
- University of Pennsylvania
- University of New South Wales
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Biochemistry › Amino Acid Enzymes and Metabolism
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Biochemical and Molecular Research
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Polyamine Metabolism and Applications
- Keywords
- Helicobacter pylori, urea cycle, arginase, ornithine transcarbamylase, argininosuccinate synthetase, argininosuccinate lyase, nitrogen metabolism, ammonia excretion, L-arginine, L-ornithine, carbamoyl phosphate
- MeSH terms
- Arginine, Argininosuccinate Lyase, Argininosuccinate Synthase, Argininosuccinic Acid, Carbamyl Phosphate, Nitrogen, Ornithine, Ornithine Carbamoyltransferase, Time Factors, Urea, Helicobacter pylori
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