Supramolecular assembly and acid resistance of Helicobacter pylori urease
@article{Ha2001SupramolecularAA, title={Supramolecular assembly and acid resistance of Helicobacter pylori urease}, author={Nam-Chul Ha and Sang-Taek Oh and Jae Young Sung and Kyeung Ah Cha and Mann-Hyung Lee and Byung-Ha Oh}, journal={Nature Structural Biology}, year={2001}, volume={8}, pages={505-509} }
Helicobacter pylori, an etiologic agent in a variety of gastroduodenal diseases, produces a large amount of urease, which is believed to neutralize gastric acid by producing ammonia for the survival of the bacteria. Up to 30% of the enzyme associates with the surface of intact cells upon lysis of neighboring bacteria. The role of the enzyme at the extracellular location has been a subject of controversy because the purified enzyme is irreversibly inactivated below pH 5. We have determined the…
397 Citations
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References
SHOWING 1-10 OF 28 REFERENCES
Characterization of the Helicobacter pylori urease and purification of its subunits.
- BiologyMicrobial pathogenesis
- 1991
Helicobacter pylori Containing Only Cytoplasmic Urease Is Susceptible to Acid
- Biology, MedicineInfection and Immunity
- 1998
It is concluded that cytoplasmic urease activity alone is not sufficient to allow survival of H. pylori in an acid environment and that the activity of surface-localized ure enzyme is essential for resistance ofH.
Surface localization of Helicobacter pylori urease and a heat shock protein homolog requires bacterial autolysis
- BiologyInfection and immunity
- 1996
Investigation of mechanisms whereby urease and HspB, a GroEL homolog, become surface associated in vitro suggests that H. pylori cells undergo spontaneous autolysis during culture and that ure enzyme and HSPB become surfaceassociated only concomitant with bacterial autolytic activity.
Purification and N-terminal analysis of urease from Helicobacter pylori
- BiologyInfection and immunity
- 1990
The amino acid sequence is conserved among ureases with one, two, and three distinct subunits, suggesting a common ancestral urease gene.
Localization of Helicobacter pylori urease and heat shock protein in human gastric biopsies
- Biology, MedicineInfection and immunity
- 1997
The results demonstrate that both urease and HspB are located within the cytoplasm of all bacteria examined in human gastric biopsies, indicating that in vivo, H. pylori has surface characteristics which enable it to adsorbed onto the surface of neighboring viable bacteria.
Purification and characterization of the urease enzymes of Helicobacter species from humans and animals
- BiologyInfection and immunity
- 1992
N-terminal amino acid sequencing of the enzyme subunits from the four species revealed high levels of homology, suggesting a common ancestral origin and an important role for the urease enzymes of these organisms.
Synthesis and activity of Helicobacter pylori urease and catalase at low pH.
- BiologyGut
- 1997
Low surrounding pH reduces activity of Urease and synthesis of nascent urease, catalase, and presumably of most other proteins, suggesting that H pylori is not acidophilic although it tolerates short-term exposure to low pH.
Purification and characterization of urease from Helicobacter pylori.
- BiologyThe Journal of biological chemistry
- 1990
The role of internal urease in acid resistance of Helicobacter pylori.
- Biology, MedicineGastroenterology
- 1998
A H+-gated urea channel: the link between Helicobacter pylori urease and gastric colonization.
- BiologyScience
- 2000
Acidic media trigger cytoplasmic urease activity of the unique human gastric pathogen Helicobacter pylori. Deletion of ureI prevents this activation of cytoplasmic urease that is essential for…