Helicobacter pylori infection is among the most prevalent infections in the world involving more than half the adult population. H. pylori infection results in active chronic gastritis, peptic ulcers and enhances the risk of gastric malignancies. It is of utmost importance to prevent H. pylori infection particularly in highly prevalent countries including Iran. The urease holoenzyme produced by...

The role of Helicobacter pylori urease in opsonization by human complement was investigated. H. pylori wild type strain N6 and isogenic mutants lacking either the large urease subunit (UreB) or an accessory urease protein (UreG) were incubated with different sera. C3b bound to the bacteria was measured by specific staining and flow cytometry. As compared with opsonization of N6 and the UreG-lac...

In this study, urease production was investigated among thirteen strains of Aspergillus niger seven strains isolated from soils of Semnan province in Iran and six strains obtained from Persian Type Culture Collection (PTCC). The enzyme production was screened in two submerged media quantitatively. The registered PTCC 5011 and the native S31 strains showed more urease production than the other e...

Metalloenzymes often require elaborate metallocenter assembly systems to create functional active sites. The medicallyimportant, dinuclear nickel enzyme urease provides an excellent model for studying metallocenter assembly. Nickel is inserted into the urease active site in a GTP-dependent process with the assistance of UreD/UreH, UreE, UreF, and UreG. These accessory proteins orchestrate apopr...

Three laboratory-prepared urease reagents were compared with a commercial preparation supplied for routine use on the Beckman Blood Urea Nitrogen Analyzer. There were discrepancies in results for urea nitrogen among the four urease reagents when matching serum and the corresponding oxalate/fluoride treated plasma were compared as measured with the Beckman Analyzer and continuous-flow (AutoAnaly...

Micromolar levels of urea [1–20 mM] on surface micromachined polysilicon cantilever beams immobilized with the enzyme urease was studied. Urea hydrolyses to ammonia and carbon dioxide which are volatile in nature. Monitoring the change in resonance frequency of a urease immobilized cantilever beam during the course of urea hydrolysis, mediated by the immobilized enzyme can give us information o...

Urease has been localized in sections of cotyledons from germinating seeds of jack bean, using FITC-labelled immunoglobulin prepared from urease antiserum raised in rabbits. The complication of lectin binding to the immunoglobulins was resolved by treatment of the sections with specific glycosides. Urease is localized in 2 sites: within the cytoplasm of storage parenchyma cells in spherical gra...