Infection with Helicobacter pyloriis the most common cause of stomach and duodenal ulcers. About more than 80 % of people are infected with H. pylori in developing countries. H. pyloriuses urease enzyme product “ammonia” in order to neutralize and protect itself from the stomach acidic condition and urease enzyme activity has been shown to be essential to the colonization of H. pylori. Inhibito...

To investigate the role played by urease during the Bordetella bronchiseptica infection process, the ability to colonise and persist in the mouse respiratory tract of a urease-negative B. bronchiseptica BB7865 and a BB7865 derivative constitutively expressing urease was compared with that of the wild-type strain. The results obtained showed that neither constitutive expression nor abolishment o...

Urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide. The ammonia (nitrogen (N) product of urease activity) is incorporated into organic compounds. Thus, urease is involved in N remobilization, as well as in primary N assimilation. Two urease isoforms have been described for soybean: the embryo-specific, encoded by the Eu1 gene, and the ubiquitous urease, encoded by Eu4. A thir...

Sustainable and rational management of agrophytocenoses depends on various bioindices and methods of application, particularly the development and protection of soil resources (Lai et al., 2002). Among other indices, enzyme activity is proposed as a universal index of soil fertility and contamination (Dilly et al., 2003). To ascertain and to make a comparison of bioactivity variation during the...

Helicobacter pylori urease requires nickel ions in the enzyme active site for catalytic activity. Nickel ions must, therefore, be actively acquired by the bacterium. NixA (high-affinity nickel transport protein)-deficient mutants of H. pylori retain significant urease activity, suggesting the presence of alternate nickel transporters. Analysis of the nucleotide sequence of the H. pylori genome ...

Background: Acid test meals may improve the accuracy of the C urea breath test (UBT). This has been attributed to changes in gastric emptying rather than to the effects of gastric pH on Helicobacter pylori urease. Aims: To determine whether enhancement of CO2 excretion in the UBT in H pylori infected volunteers by acidification of a test meal is due to a delay in gastric emptying. Methods: Urea...

For decades, Hibiscus sabdariffa L. and its phytochemicals have been shown to possess a wide range of pharmacologic properties. In this study, aqueous extract of Hibiscus sabdariffa (AEHS) and its bioactive constituent protocatechuic acid (PCA), have been evaluated in vitro for their antiviral activity against HSV-2 clinical isolates and anti-enzymatic activity against urease. Antiherpetic acti...

Yersinia enterocolitica produces the enzyme urease which hydrolyses urea, resulting in the production of carbonic acid and ammonia and a net increase in pH. In the presence of urea, urease enhances survival of Y. enterocolitica in the stomach and presumably in other acidic environments the bacteria encounter during the course of infection. In this study we show that Y. enterocolitica urease is ...

The urease enzyme of Campylobacter pylori was studied and compared with that of a related spiral-shaped bacterium, St1, isolated from the rodent ileum. Both bacteria possessed constitutive urease enzymes with activities up to 20-70 times that of Proteus vulgaris. This activity was retained on SDS-polyacrylamide gels. A major catalytic subunit of mol. wt 300,000 was located for all (six) strains...