Cashmirins A (1) and B (2), new prenylated coumarins, have been isolated from the EtOAc- soluble fraction of whole plant Sorbus cashmiriana Hedlung, Monog. along with seselin (3), scopoletin (4), 3-hydroxyxanthyletin (5) luteolin (6), reported for first time this species. Their structures were elucidated by spectroscopic techniques including MS, 1D 2D NMR spectroscopy. Both compounds 1 2 invest...

The nickel-containing enzyme urease is an essential colonization factor of the gastric pathogen Helicobacter pylori, as it allows the bacterium to survive the acidic conditions in the gastric mucosa. Although urease can represents up to 10% of the total protein content of H. pylori, expression of urease genes is thought to be constitutive. Here it is demonstrated that H. pylori regulates the ex...

Studies with two uropathogenic urease-producing Escherichia coli strains, 1021 and 1440, indicated that the urease genes of each are distinct. Recombinant plasmids encoding urease activity from E. coli 1021 and 1440 differed in their restriction endonuclease cleavage sites and showed minimal DNA hybridization under stringent conditions. The polypeptides encoded by the DNA fragments containing t...

Urease is a nickel-containing urea hydrolase involved in nitrogen recycling from ureide, purine, and arginine catabolism in plants. The process of urease activation by incorporation of nickel into the active site is a prime example of chaperone-mediated metal transfer to an enzyme. Four urease accessory proteins are required for activation in Klebsiella aerogenes. In plants urease accessory pro...

Urease was purified 500-fold to electrophoretic homogeneity from ground, dry soybeans. Sodium dodecyl sulfate-acrylamide gel electrophoresis indicates a subunit size of 93,500 daltons which is identical with that of jack bean urease. In solutions of high ionic strength, there exists a single urease species (species 1) with a size of about 480,000 daltons based on agarose column chromatography a...

Helicobacter pylori is a human pathogen that infects over 50% of the population worldwide. It is the most important etiologic agent of gastroduodenal ulcers and malignancies. Helicobacter pylori urease enzyme is considered the main factor for the organism's colonization in the gastroduodenal mucosa. Hens immunized with the purified urease produce a highly specific anti-H. pylori urease immunogl...

Helicobacter pylori, an important etiologic agent in a variety of gastroduodenal diseases, produces large amounts of urease as an essential colonization factor. We have demonstrated previously that urease is located within the cytoplasm and on the surface of H. pylori both in vivo and in stationary-phase culture. The purpose of the present study was to assess the relative contributions of cytop...

The accumulation of environmental contaminant such as fluoride in wetlands especially rice fields is increasing drastically by the action fertilizers, pesticides, mining, waste disposal, and atmospheric pollution which Kuttanad, unique tropical wetland agro ecosystem not an exception. Accumulation excess F- environment poses serious burden to all organisms. Since soil microbial enzymes respond ...

The aim of this work was to evaluate the effect of two different humic acid (HA) fractions, high molecular weight (HMW 100–300 kDa) and low molecular weight (LMW 10–20 kDa), extracted from peat on the activity and stability of Jack Bean urease. HMW HA significantly inhibited urease activity at pH 6.0 but did not influence the activity at pH 7.0 and 8.0. HMW HA stabilised urease activity over a ...

Purpose: To develop a multiplex-urease PCR assay specific for ureA and ureB genes directly from gastric biopsy specimens and compare the results of multiplex-urease PCR assay with rapid urease test (RUT) and histopathology. Methodology: This study was conducted on 109 patients. A RUT was run; histopathological staining and multiplex urease PCR were applied to biopsy specimen to detect H. pylori...