Urease activities of anaerobic bacteria that constituted predominant gut flora were examined. It was demonstrated that some strains of Eubacterium aerofaciens, E. lentum, and Peptostreptococcus products produced urease. They were the most numerous species in human feces. All strains of Bifidobacterium infantis and some strains of Bacteroides multiacidus, B. bifidum, Clostridium symbiosum, Fusob...

A simple, reproducible and high yield method of Helicobacter pylori urease enzyme purification was developed using a heparinoid (Cellufine sulfate) affinity gel. The purification method involved two sequential steps using the same gel that takes advantage of the differential affinity of urease to the heparinoid at two levels of hydrogen ion concentration. SDS-polyacrylamide gel electrophoresis ...

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 inhibitor [N-(n-butyl) thiophosphoric triamide (NBPT)] and nitrification (NI) (3,4-dimethylpyrazole phosphate) have been used to reduce nitrogen (N) losses from urea-based fertilizers. This study evaluated the effect of temperature, NBPT, NI on kinetic thermodynamic properties urea hydrolysis in six soils. Soils were amended (250 kg N·ha ?1 ) with (UR), NBPT treated (UR ), or + DI incuba...

Fast protein liquid chromatography and SDS-PAGE have been used to isolate and purify Helicobacter pylori urease. A nickel component of the urease was detected in the purified proteins by atomic absorption spectroscopy. The nickel was present only in the 61 kDa polypeptide and in the ratio of between five and six atoms to one molecule of urease, suggesting a hexameric structure. These results ar...

Helicobacter hepaticus causes disease in the liver and lower intestinal tract of mice. It is strongly urease positive, although it does not live in an acidic environment. The H. hepaticus urease gene cluster was expressed in Escherichia coli with and without coexpression of the Helicobacter pylori nickel transporter NixA. As for H. pylori, it was difficult to obtain enzymatic activity from reco...

A growth medium and test were developed for rapid detection of urease in fermentative anaerobic bacteria. Using nonselective rumen fluid roll-tube agar medium and the new test, it was confirmed that Peptostreptococcus productus is often the most numerous urease-forming species in human feces. Also, some fecal strains of Ruminococcus albus, Clostridium innocuum, and Clostridium beijerinckii prod...

The Corynebacterium glutamicum genes encoding urease were isolated and sequenced. While ureA, ureB and ureC are encoding structural subunits of urease, ureE, ureF, ureG and ureD are encoding accessory proteins. As deduced from DNA sequence analyses, the ure genes are transcriptionally coupled, this was proven by RT-PCR at least for ureABC. Gene disruption experiments revealed that both structur...