Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.3.4.6 (urease)
 7,490 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

L-Canavanine competes with L-arginine for incorporation into vitellogenin secreted in vitro by the fat body of the female locust Locusta migratoria migratorioides. Incorporation of L-[guanidinooxy-14C]canavanine into vitellogenin has been established unequivocally by combined arginase and urease hydrolyses of the acid hydrolysate of antibody-precipitated canavanyl vitellogenin. Continued exposure of the fat body to canavanine decreases in vitro protein secretion but the proportion of canavanyl vitellogenin to native vitellogenin increases. Canavanine-mediated inhibition of fat body protein secretion is dependent on both the canavanine concentration and the arginine retention by the fat body. Canavanine replaces about 10% of the arginyl residues of canavanyl vitellogenin. The electrophoretic mobility of canavanyl vitellogenin is greater than that of native vitellogenin but the ability of this aberrant protein to react with vitellogenin antibody is unimpaired.
Proc Natl Acad Sci U S A 1981 Sep
PMID:In vitro incorporation of L-canavanine into vitellogenin of the fat body of the migratory locust Locusta migratoria migratorioides. 694 85

We tested the inhibitory power and urinary excretion of several derivatives of hippurohydroxamic acid, including some newly synthesized compounds. m-Methoxyhippurohydroxamic acid (UCD II) strongly inhibited urease activity and high urinary excretion after oral administration to rats. UCD II inhibited the alkalinization of infected urine in vitro and in vivo and prevented bladder stone formation when it was orally administered to rats with urinary tract infection caused by Proteus mirabilis. The clinical application of UCD II to the prevention of pathologic sequelae of urinary infection with urease-producing bacteria awaits evaluation of the safety of the compound.
Invest Urol 1980 Sep
PMID:Prevention of infected urinary stones in rats by urease inhibitor: a new hydroxamic acid derivative. 699 28

The ureases of Proteus mirabilis, Proteus vulgaris, and Proteus rettgeri are inducible by urea. Induction is increased when both urea and acetohydroxamic acid, an inhibitor of urease, are present during bacterial growth. Acetohydroxamic acid alone does not cause induction, but, by preventing the hydrolysis of urea, it minimizes pH increases and allows induction to occur much more effectively. The ureases of Proteus morganii and other bacterial genera are not inducible by this method. The relevance of our findings to the formation and management of infection stones is discussed.
Invest Urol 1980 Sep
PMID:The effect of acetohydroxamic acid on the induction of bacterial ureases. 699 29

Office patients with a positive urinary tract infection (UTI) were screened for the presence of a urease positive microorganism by a rapid biotyping. Approximately 12 per cent of the UTI episodes were caused by a urease positive organism. Over 95 per cent of Proteus and Klebisella isolates were urease positive, and a lesser percentage of Pseudomonas. No Escherichia coli were urease positive. Determination of urease production can be assessed by the standard API (Analytab Products Inc.) biotyping technique for gram negative organisms. A specific digit in the biotype code indicates urease activity.
Urology 1980 Sep
PMID:Office practice survey of urease positive bacterial pathogens causing urinary tract infections. 699 99

The apparent I50 values of various hippurohydroxamic acids against urease activity of sword bean were mostly 0.5 to 2.0 microM regardless of hydrophobicity of their substituents. However, the marked increase of hydrophilicity caused by substitution of trimethoxy groups conspicuously decreased the inhibitory potency. Methylation at alpha-position of the hydroxamic acid group in these compounds remarkably decreased the inhibitory potency, probably owing to steric hindrance by the alpha-methyl group. Thenoyl-, furoyl- and nicotino-glycinohydroxamic acids which are bioisostereomers of hippurohydroxamic acid had I50 values of 0.64, 1.3 and 5.3 microM, respectively. Furthermore, the inhibitory potency of some substituted hippurohydroxamic acids against the ureolytic activity of intact Proteus mirabilis isolated from patients with urinary tract infection, were half to one-tenth of those against urease activity of sword bean. On the other hand, m- and p-nitro-, m- and p-methoxy-, m- and p-acetylamino-hippurohydroxamic acid and furoylglycinohydroxamic acid showed high urinary excretion rates of 14 to 16% of the doses administered orally to rats, while most of the others had excretion rates of about 3 to 5%.
J Pharmacobiodyn 1980 Sep
PMID:Therapy for urolithiasis by hydroxamic acids. II. Urease inhibitory potency and urinary excretion rate of hippurohydroxamic acid derivatives. 700 13

Hydroxamic acid, a potent urease inhibitor, having a high urinary excretion rate is expected to be a therapeutic agent for urolithiasis caused by urea-splitting bacterial infection of the urinary tract. Twenty-one new derivatives of N-aliphatic-acylglycinohydroxamic acids (GHAs) were synthesized, and their inhibitory potencies against the urease activity of sword bean in a phosphate buffer and against the ureolytic activity of Proteus mirabilis in human urine, and their urinary excretion rates in rats were also measured for this purpose I50 values of most of GHAs against the urease activity of sword bean were about 1 to 10 microM and 2-ethyl-n-butyroyl GHA was the most potent inhibitor with the value of 0.79 microM. I50 values of most of the GHAs against the ureolytic activity of Proteus mirabilis were about 5 to 50 microM and n-nonaroyl GHA was the most potent inhibitor with the value of 3.6 microM. 2,2-Dimethylpropionyl GHA had the highest urinary excretion rate with the recovery of 11%. Routes of administration of 2,2-dimethylpropionyl GHA and sex of rats used did not affect the amount of urinary excretion at all. The results in this report suggest that DL 2-methyl-n-butyroyl, 2-ethyl-n-butyroyl and 2,2-dimethylpropionyl GHA are the most hopeful therapeutic agents for urolithiasis among them.
J Pharmacobiodyn 1980 Sep
PMID:Therapy for urolithiasis by hydroxamic acids. III. Urease inhibitory potency and urinary excretion rate of N-acylglycinohydroxamic acids. 700 14

A semisolid urea-motility-indole medium designed for detection in Enterobacteriaceae of urease activity, motility, and indole production in one tube was prepared and evaluated. The formulation of the medium was similar to that of Christensen urea agar, but the agar concentration was 0.2%, and 1% tryptone was added. Results with 687 strains of Enterobacteriaceae were the same as those obtained with standard test media (98% overall agreement). The urea-motility-indole medium was also used in combination with Kligler iron agar for the recognition and differentiation of Salmonella and Shigella species from colonies picked from plating media in fecal cultures. This combination was compared with the combination of Kligler iron agar and lysine iron agar with 507 strains of non-lactose-fermenting Enterobacteriaceae. Although both combinations enabled the presumptive recognition and differentiation of Salmonella and Shigella species, an analysis of data indicated that the combination of Kligler iron agar and urea-motility-indole medium performed better than the combination of Kligler iron agar and lysine iron agar in detecting Salmonella and Shigella species.
J Clin Microbiol 1980 Sep
PMID:Evaluation of Urea-motility-indole medium for recognition and differentiation of Salmonella and Shigella species in stool cultures. 721 32

A minor modification in the automated analytical system of the official AOAC semiautomated method for determining crude proteins results in an automated method for determining urea and ammoniacal nitrogen in animal feeds and their ingredients. Urease enzyme which has high activity, yields a clear solution in water, has low ammonia impurity, and is inexpensive is used in the automated method. Weights from 1 to 2.5 g feed sample are dissolved in water, and sample solutions are analyzed at the rate of 40 samples/h. Five AAFCO feed check samples were analyzed repeatedly by the automated method, and results were compared with the grand averages from the check sample reports. The official AOAC manual urease method was used by AAFCO participants. Average recovery of urea and ammoniacal nitrogen was 100.6% by the automated method relative to the AAFCO reported averages. The range of recoveries as 98.5-102.7%. The non-protein nitrogen (NPN) concentrations, expressed as protein equivalent, ranged from 3.40 to 63.04% protein on these samples. The average relative standard deviation for the automated analyses was 0.77%, compared with 1.54% for the manual method. This method is an important adjunct to laboratories using or considering use of the semiautomated method for crude protein and needing further information on NPN.
J Assoc Off Anal Chem 1981 Sep
PMID:Automated determination of urea and ammoniacal nitrogen (NPN) in animal feeds. 728 6

An abbreviated procedure for the biochemical identification of Yersinia enterocolitica isolated from food enrichments on CIN (cefsulodin-irgasan-novobiocin) agar was investigated. A total of 170 colonies resembling Y. enterocolitica in colonial morphology and appearance on CIN agar were selected for identification using API strips. Ninety-three of these isolates were examined with the PathoTec ornithine decarboxylase, Voges-Proskauer, and urease test strips. The PathoTec urease strip alone was adequate for identification of all isolates of Y. enterocolitica. Christensen's urea agar was applied to the remaining 77 isolates and found less specific in the 1 isolate of Enterobacter agglomerans was urease positive along with 10 isolates of Y. enterocolitica. CIN agar is a highly specific medium for isolation of Y. enterocolitica, requiring only Kligler iron agar and urea slants for confirmation of presumptive colonies.
Can J Microbiol 1981 Sep
PMID:An abbreviated scheme for identification of Yersinia enterocolitica isolated from food enrichments on CIN (cefsulodin-irgasan-novobiocin) agar. 730 81

Urea is extracted from rodent urine-contaminated material with hot acetone. After the extract is evaporated to dryness, aqueous urease solution is added to produce ammonia and carbon dioxide. A blue product, indophenol, is formed by the reaction of ammonia with phenol in the presence of hypochlorite. Absorbance is maximum at 625 nm. Presence of urea is easily detected at 4 microgram. Detection of urine contamination in various materials is compared with detection by the AOAC urease-H2PtCl6 test.
J Assoc Off Anal Chem 1980 Sep
PMID:Spectrophotometric determination of urea in urine stains on foods and containers. 741 Mar 9


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