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)

Rats implanted with subcutaneous or intraperitoneal osmotic minipumps infusing 0.8-1.25 IU urease/kg/h develop sustained hyperammonemia (range 137-497 microM, controls 88 +/- 51 microM +/- SD) for 5-7 days. Glutamine levels are also significantly elevated in plasma (677 +/- 166 versus 428 +/- 122 microM) and cerebral cortex (13.2 +/- 9.8 versus 4.7 +/- 2.8 nmol/mg tissue). Neurobehavioral abnormalities include decreased food intake and increased stereotypic activity. Increased serotonin turnover was suggested by elevated levels of tryptophan and 5-hydroxyindoleacetic acid in cerebral cortex, brain stem, and cerebellum of urease-infused compared to sham-operated animals. There were no changes in norepinephrine or gamma aminobutyric acid, and there was no correlation between the degree of hyperammonemia or glutaminemia and brain levels of tryptophan or biogenic amines. Animals receiving a tryptophan-deficient diet had significantly lower levels of tryptophan and 5-hydroxyindoleacetic acid in brain regions compared to animals receiving a normal tryptophan intake, under both control and hyperammonemic conditions. Despite the prevention of increased serotonin flux in hyperammonemic animals receiving a tryptophan-deficient diet, food intake and weight declined and there was increased stereotypic behavior.
Pediatr Res 1986 Dec
PMID:Behavioral and neurotransmitter changes in the urease-infused rat: a model of congenital hyperammonemia. 379 24

Acetohydroxamic acid (AHA), a potent urease inhibitor used for treatment of infection-induced struvite urolithiasis, was teratogenic after administration of 25 mg of AHA/kg of body weight/day orally to 5 clinically normal Beagles from the onset of proestrus until parturition. Thirty pups exposed to AHA in utero developed anomalies of the skeletal system, heart, and ventral midline. Cardiac anomalies included atrial septal defects (20%), ventricular septal defects (3%), and atrial and ventricular septal defects (3%). Skeletal anomalies included coccygeal hemivertebrae and fused coccygeal vertebrae (50%), supernumerary vertebrae (67%), supernumerary ribs (50%), duplicated sternebrae (3%), and lumbar hemivertebrae (3%). Defects of the ventral midline of the abdominal wall occurred in 20% of AHA-exposed pups. Other abnormalities included retarded growth, high neonatal mortality, and a decreased number of circulating RBC, compared with those in 30 control pups born to 5 Beagles given a placebo. Adverse effects of AHA in pregnant Beagles were limited to morphologic alterations (Howell-Jolly bodies, spherocytes, and target cells) in a small number of circulating RBC. Slight neutrophilic leukocytosis and monocytosis occurred between 0 and 30 days of pregnancy in dogs given AHA, compared with those in controls. Seemingly, AHA did not influence fertility, conception rate, or length of gestation.
Am J Vet Res 1986 Dec
PMID:Teratogenic effect of acetohydroxamic acid in clinically normal beagles. 380 Jan 19

Benzoyl- and isopentenoyl phosphoric triamides (BPA and IPA) strongly inhibited urease activities from jack bean, soybean, watermelon seed, Proteus mirabilis, P. rettgeri, P. vulgaris, Mycobacterium smegmatis, and Ureaplasma urealyticum. Their I50 values (the final concentration causing 50% inhibition), independent of enzyme source, were 2-21 nM, which are about 1,000-fold lower than that of caprylohydroxamic acid, one of the most potent urease inhibitors. ATP-urea amidolyase activity was inhibited 50% by BPA at a higher concentration of 0.28 mM, but was not affected by IPA even at 1.3 mM. Thirteen kinds of hydrolases (trypsin, chymotrypsin, thermolysin, leucine aminopeptidase, papain, lipase, alpha-amylase, glucuronidase, asparaginase, arylsulfatase, alkaline phosphatase, acid phosphatase, and true cholinesterase), two oxidoreductases (catalase and alcohol dehydrogenase), three transferases (glutamic-oxaloacetic aminotransferase, gamma-glutamyl transpeptidase, and arylsulfotransferase) and two kinases (pyruvate kinase and creatine kinase) were not affected at all even at 1 mM BPA and IPA. Exceptionally, pseudo-cholinesterase from human serum was inhibited by BPA and IPA, whose I50 values were 70 nM and 10 muM, respectively, using acetylthiocholine as a substrate. These values increased to 0.55 muM and 54 muM, respectively, when acetylcholine was used as a substrate. These results show that N-acylphosphoric triamides potently and specifically inhibit urease activity at concentrations of nM order.
J Biochem 1985 Dec
PMID:Specific inhibition of urease by N-acylphosphoric triamides. 384 42

In our laboratory, selected strains of Gram-negative rods from urine samples are identified as Escherichia coli on the basis of smell and morphology on lactose agar. To investigate the accuracy of this routine practice, 211 consecutive strains were tested in the urea-indole tube of the Three-tube method (3-TM), in the PGUA test detecting beta-glucuronidase activity and in the Simmons' citrate test, to select the strains that were non-E. coli. Additional 1022 strains were tested by the indole and urease tests of the 3-TM only. The identification of E. coli based on the macroscopic evaluation of colonies on lactose agar gave correct results for 99.1% of the strains. Citrobacter freundii was the most frequent cause of erroneous identification.
Acta Pathol Microbiol Immunol Scand B 1985 Dec
PMID:Rapid identification of Escherichia coli from routine urine specimens based on macroscopic criteria. 391 21

Of 30 sows from a herd believed to be free of Haemophilus pleuropneumoniae infection, 2 had complement-fixing antibodies to H. pleuropneumoniae serotype 5. Necropsy and microbiological examination of the two sows revealed no evidence of H. pleuropneumoniae infection; however, Haemophilus taxon "minor group" and a urease-negative, indole-positive Haemophilus sp. were isolated from numerous respiratory tract sites in both sows. Isolation of these Haemophilus spp. was facilitated by serially diluting specimens in two broth media. Pigs from a closed, respiratory disease-free herd were inoculated with four strains of Haemophilus taxon "minor group" to determine whether the organism induces antibodies which cross-react with H. pleuropneumoniae in the complement fixation test. Antigenic heterogeneity among the taxon "minor group" strains was apparent; however, antibodies cross-reacting between these strains and H. pleuropneumoniae serotypes 1 through 5 and 7 were not detected.
J Clin Microbiol 1985 Dec
PMID:Characterization of Haemophilus spp. isolated from healthy swine and evaluation of cross-reactivity of complement-fixing antibodies to Haemophilus pleuropneumoniae and Haemophilus taxon "minor group". 406 24

Detection and intensity of urease activity in enterobacteriaceae greatly varies as a function of the media or techniques used, or both. A comparative investigation on several solid and liquid media led us to the following conclusions. (i) Detection of Proteus spp. can be adequately performed with the highly selective solid medium described by Cook (1948), as well as with the different liquid media described (Stuart standard and rapid media; Elek medium). (ii) Detection of Klebsiella should be based upon urease production on solid media with low buffer capacity (Christensen, 1946). (iii) For the identification of Yersinia, either the solid Christensen urea agar or the rapid Elek technique give optimal results.
Appl Microbiol 1973 Dec
PMID:Urease activity of enterobacteriaceae: which medium to choose. 458 92

The 10 biochemical test strips included in the PathoTec Rapid I-D System were evaluated for accuracy as compared to standard tests and for efficacy in identification of 193 gram-negative bacilli. The test agreement was 100% for oxidase and phenylalanine deaminase, 99% for indole, nitrate, and Voges-Proskauer, 98% for malonate, 97% for lysine decarboxylase, 90% for urease, 84% for H(2)S, and 75% for esculin hydrolysis. Most of the commonly isolated Enterobacteriaceae were identified correctly within 4 h. Errors in identification of Proteus morganii and P. rettgeri occurred because of positive H(2)S tests on the PathoTec strips with these organisms.
Appl Microbiol 1973 Dec
PMID:Evaluation of the PathoTec "Rapid I-D System". 458 96

A well-mixed powder consisting of dry urea and urease exposed to air containing discrete amounts of water vapor showed a release of carbon-14 dioxide above 60-percent relative humidity. The relative activity of urease followed the water-vapor adsorption isotherm of urease. The minimum amount of water required for the reaction observed was 1.3 moles per mole of side-chain polar groups of the urease protein.
Science 1967 Dec 22
PMID:Enzyme reaction rates at limited water activities. 606 Mar 60

A spot test for the detection of urease activity was developed and evaluated with 761 strains of gram-negative bacteria. The test was compared with the conventional Christensen urea agar slants and urease test on the Vitek Enterobacteriaceae card (Vitek Systems, Inc., St. Ana, Mo.). Of the 348 strains of the Proteus-Providencia-Morganella group that were urease positive, 327 (94%) yielded positive results within 1 min, and all strains yielded positive results within 2 min. All these organisms also gave a positive urease reaction on the Vitek Enterobacteriaceae card test within 5 h and on the Christensen urea agar slants in 4 to 48 h. All the bacteria that did not hydrolyze urea by these two tests also remained negative by the spot test.
J Clin Microbiol 1984 Dec
PMID:Simple spot test for rapid detection of urease activity. 639 23

Simple and rapid Bactec methodologies for the determination of neat (unaltered) and heat stable urease activity of mycobacteria are presented. Clinical isolates (63) and stock cultures (32)--consisting of: M. tuberculosis (19), M. bovis (5), M. kansasii (15), M. marinum (4), M. simiae (3), M. scrofulaceum (16), M. gordonae (6), M. szulgai (6), M. flavescens (1), M. gastri (1), M. intracellulare (6), M. fortuitum-chelonei complex (12), and M. smegmatis (1)--were tested for neat urease activity by Bactec radiometry. Mycobacterial isolates (50-100 mg wet weight) were incubated at 35 degrees C for 30 minutes with microCi14C-urea. Urease-positive mycobacteria gave Bactec growth index (GI) values greater than 100 units, whereas urease-negative species gave values less than 10 GI units. Eighty-three isolates possessing neat urease activity were heated at 80 degrees C for 30 minutes followed by incubation at 35 degrees C for 30 minutes with 1 microCi14C-urea. Mycobacterium tuberculosis-bovis complex demonstrated heat-stable urease activity (GI more than 130 units) and could be distinguished from mycobacteria other than tuberculosis (MOTT), which gave GI values equal to or less than 40 units.
Am J Med Technol 1983 Dec
PMID:Rapid presumptive identification of the Mycobacterium tuberculosis-bovis complex by radiometric determination of heat stable urease. 642 56


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