We examined the effects of urease and hydrogenase assembly gene deletions on NikR activation in H. pylori strains 26695 and G27. The loss of any component of urease assembly increased NikR activity under Ni2+-limiting conditions, as measured by reduced transcript levels and 63Ni accumulation. Additionally, SlyD functioned in urease assembly in strain 26695.

In a wheat/maize rotation system, nitrogen (N) accounts for large proportion of basal fertilizer, but soil N loss and the resulting environmental risk simultaneously exist worldwide. This study applied different urease/nitrification inhibitors together with fertilizers investigated their effects on level grain yield. Six stabilizing combinations consisted two urease (HQ NBPT) three nitrificatio...

CONTEXT The correct diagnosis and effective treatment of Helicobacter pylori gastric infection are essential in controlling this infection. OBJECTIVE To compare the diagnostic value of three tests based in endoscopic gastric biopsies histopathological evaluation with hematoxylin-eosin (H-E) staining, urease rapid test and microbiological culture for detecting Helicobacter pylori active infect...

Early studies of a ureB mutant derivative of Helicobacter pylori had suggested that urease is needed for motility and that urease action helps energize flagellar rotation. Here we report experiments showing that motility is unaffected by deletion of ureA and ureB (urease genes) or by inactivation of ureB alone, especially if H. pylori strains used as recipients for transformation with mutant al...

Helicobacter mustelae, a gastric pathogen of ferrets, synthesizes a distinct iron-dependent urease in addition to its archetypical nickel-containing enzyme. The iron-urease is oxygen-labile, with the inactive protein exhibiting a methemerythrin-like electronic spectrum. Significantly, incubation of the oxidized protein with dithionite under anaerobic conditions leads to restoration of activity ...

Seventy-five consecutive patients referred for upper gastrointestinal tract endoscopy were evaluated for Campylobacter pylori infection by pathology, culture, and a biochemical test to detect bacterial urease. Forty-eight patients (64%) had C. pylori present based on pathology or culture or both. Thirty-two urease tests were positive after 1 h, all in patients with C. pylori detected by the two...

Urease has attracted much attention, as it is directly involved in the formation of infection stones and contributes to the pathogenesis of urolithiasis, pyelonephritis, ammonia and hepatic encephalopathy, hepatic coma and urinary catheter encrustation. Moreover, urease is the major cause of pathologies induced by H. pylori, such as gastritis and peptic ulcer. In the present work, the new natur...

Jack bean urease catalyzes the decomposition of urea into ammonia, which in turn increases the pH of the surrounding medium. Based on these two properties, we have investigated the antitumor effects of urease in vitro and in vivo on human lung and breast cancer cell lines either by the enzyme itself or in combination with other chemotherapeutic drugs. First, through the generation of toxic ammo...

Helicobacter pylori infection causes chronic active gastritis that after many years of infection can develop into peptic ulceration or gastric adenocarcinoma. The bacterium is highly adapted to surviving in the gastric environment and a key adaptation is the virulence factor urease. Although widely postulated, the requirement of urease expression for persistent infection has not been elucidated...