Catalytic buffering is an advanced method of pH control for the enzyme-based Advanced Catalytic Enzyme System (ACES) and oxidative surety agent decontamination technologies. Ammonia production from urea by urease neutralizes the production of Oalkylphosphonic acids resulting from the hydrolysis of Nerve agents such as Sarin and VX. Fluoride production from Sarin hydrolysis inhibits native ureas...

A novel method for the rapid modification of fullerene for subsequent enzyme attachment to create a potentiometric biosensor is presented. Urease was immobilized onto the modified fullerene nanomaterial. The modified fullerene-immobilized urease (C60-urease) bioconjugate has been confirmed to catalyze the hydrolysis of urea in solution. The biomaterial was then deposited on a screen-printed ele...

Nickel-containing urease from Klebsiella aerogenes requires four accessory proteins for proper active site metalation. The metallochaperone UreE delivers nickel to UreG, a GTPase that forms a UreD/UreF/UreG complex, which binds to urease apoprotein via UreD. Prior in silico analysis of the homologous, structurally characterized UreH/UreF/UreG complex from Helicobacter pylori identified a water ...

The enzymatic activity of Helicobacter pylori's urease neutralises stomach acidity, thereby promoting infection by this pathogen. Urease protein has also been found to interact with host cells in vitro, although this property's possible functional importance has not been studied in vivo. To test for a role of the urease surface in the host/pathogen interaction, surface exposed loops that displa...

Importance of urease activity on pathogenic differences among Brucella species was evaluated. In cell-free extracts, the B. suis urease showed 12 times greater specific activity than the B. melitensis urease. When Fisher-344 rats were inoculated intraperitoneally (IP), at 1 week post-inoculation (PI), B. melitensis wild type 16 M was recovered from spleens and livers in greater numbers than B. ...

Urease was purified 800-fold and partially characterized from Proteus mirabilis, the predominant microorganism associated with urinary stones. Boric acid is a rapid reversible competitive inhibitor of urease. The pH-dependence of inhibition exhibited pKa values of 6.25 and 9.3, where the latter value is probably due to the inherent pKa of boric acid. Three boronic acids also were shown to inhib...

Two 21-d trials were conducted to evaluate the effect of heating time and sodium metabisulfite (SMBS) on the nutritional value of full-fat soybeans for chicks. In Trial 1, four pen-replicates of eight chicks each were fed corn-based diets (19% CP; 3,167 kcal of ME/kg) containing either 44% CP soybean meal or full-fat soybeans. The soybeans either were unheated or were autoclaved at 121 degrees ...

Title of Document: REGULATION OF ESTUARINE PHYTOPLANKTON AND BACTERIAL UREA UPTAKE AND UREASE ACTIVITY BY ENVIRONMENTAL FACTORS Caroline Miller Solomon, Ph.D., 2006 Directed By: Professor Patricia M. Glibert Marine Estuarine Environmental Science The regulation by environmental factors of two enzymes involved with urea utilization – urea transport and urease – in estuarine phytoplankton and bac...

BACKGROUND/AIMS The influence of different media on the validity of the rapid urease test, including accuracy, reaction time and cost-effectiveness is evaluated. METHODOLOGY Biopsies were obtained from the antral and body mucosa of 100 KMUH patients (51 men, 49 women; mean age: 54.0 years, range: 21-79 years old) undergoing gastroendoscopy due to dyspepsia. None of the patients had received a...