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)

Sera from clinically immune individuals comprising 10 hospitalised patients (Group I), 30 persons residing in a malaria endemic area in Thailand (Group II) and 8 persons from a hyperendemic area in Ivory Coast (Group III) were tested by the parasite growth inhibition (PGI), indirect fluorescent antibody test of ring-infected erythrocyte surface antigen (RESA-IFA), urease-ELISA and Western blot. Paired sera from patients recovering from malaria (Group IV) as well as sera from blood donors were also tested. In the PGI test, sera were tested against three uncloned isolates of P. falciparum comprising SO, I4 and AE9 (PGI-SO, PGI-I4 and PGI-AE9 respectively). When growth inhibition of greater than or equal to 30% against any one of the three isolates was considered positive, the positive rate for the combined Groups I, II and III was 78.7%. Further analysis showed that the positive rates for PGI-SO, PGI-I4 and PGI-AE9 were 63.8%, 59.5% and 59.5% respectively and were not significantly different (p greater than 0.05). Comparison between PGI-SO, PGI-I4 and PGI-AE9 activities of Groups I, II and III sera showed no significant differences in any comparison groups except with PGI-AE9 in which Group III sera were more frequently positive than Group II sera (p = 0.004). Follow-up of PGI-SO and PGI-AE9 activities in Group IV patients showed mostly a decrease or no change in the activities of the convalescent sera taken 63 days later. RESA-IFA positive rate in the combined Groups I, II and III sera was 91.7%. There were no significant differences either in the seropositive rates or in the geometric mean antibody titers (GMT) between Groups I, II and III sera. Follow-up in Group IV patients showed no change in antibody titers in 64% of cases, decrease and increase in titers in 29% and 7% of cases respectively. The urease-ELISA seropositive rate in the combined Groups (I, II and III) was 89.5% which is not significantly different from that of RESA-IFA (p greater than 0.05). Comparison between individual Groups (I, II and III) likewise showed no significant differences in both GMT and seropositive rates. Follow-up in Group IV sera showed either no change or a decrease in antibody titers in 55.6% and 44.4% of cases respectively.(ABSTRACT TRUNCATED AT 400 WORDS)
Southeast Asian J Trop Med Public Health 1989 Sep
PMID:Assessment of putative tests for protective immunity to falciparum malaria. 269 85

We developed a buffered azide-free urea medium which is sensitive, specific, and nontoxic for rapid detection of Campylobacter pylori in gastric biopsies. Detection of urease produced by the organism provides the basis for the test. The substrate is urea in monobasic sodium phosphate buffer, and phenol red provides indication of the pH change that results from urease activity. A rapid change from yellow to red occurs in the presence of C. pylori, even at low concentrations of the organism. A slower color change occurs with higher concentrations of other urease producers, such as Yersinia enterocolitica and Proteus mirabilis. Experience with 51 patients with our medium showed excellent results in detection of C. pylori in gastric mucosal biopsies. In clinical research and practice, a rapid bedside test will be helpful for rapid diagnosis of C. pylori-positive patients.
J Clin Microbiol 1989 Sep
PMID:Optimization of a medium for the rapid urease test for detection of Campylobacter pylori in gastric antral biopsies. 277 71

The predominant ureolytic bacteria in the pig large intestine were determined while growing pigs were fed a basal diet or basal diet plus copper sulfate, Aureo SP250, or clinoptilolite. Fecal samples were collected from four pigs fed each diet at 3, 9, and 14 weeks and analyzed for total colony counts and percent ureolytic bacteria. Fecal urease activity, ammonia nitrogen, and identity of the ureolytic bacteria were determined at 14 weeks. Copper sulfate and Aureo SP250 reduced the number of ureolytic organisms, with a marked decrease occurring in the Streptococcus spp., which made up 74% of the ureolytic isolates from the pigs on the basal diet. Other ureolytic species detected at lower concentrations were Staphylococcus spp., Selenomonas ruminantium, Bacteroides multiacidus, and Eubacterium limosum. Copper sulfate also reduced fecal urease activity (P less than 0.10). Fecal ammonia concentrations were not different between pigs fed the various diets. These data suggest that the streptococci are the most numerous ureolytic species in the pig intestinal tract and are significantly reduced by copper sulfate and Aureo SP250; however, only copper sulfate reduced intestinal urease activity.
Appl Environ Microbiol 1987 Sep
PMID:Effect of dietary copper sulfate, Aureo SP250, or clinoptilolite on ureolytic bacteria found in the pig large intestine. 282 7

Six conventional biochemical tests were combined to produce an identification scheme. These tests included decarboxylation of lysine and ornithine, fermentation of glucose and cellobiose, indole production and urease production. Three hundred antibiotic resistant coliforms from urine specimens were tested by this scheme and also by the API 20E for comparison. Two hundred and seventy nine (93%) of organisms were correctly identified using the six tests, 17 (5.7%) were referred for further study, and four (1.3%) were misidentified. It is concluded that this combination of tests provides an inexpensive, accurate, and rapid tool for identification.
J Clin Pathol 1988 Sep
PMID:Rapid conventional scheme for biochemical identification of antibiotic resistant enterobacteriaceae isolates from urine. 305 81

The urease enzyme of Campylobacter pylori was studied and compared with that of a related spiral-shaped bacterium, St1, isolated from the rodent ileum. Both bacteria possessed constitutive urease enzymes with activities up to 20-70 times that of Proteus vulgaris. This activity was retained on SDS-polyacrylamide gels. A major catalytic subunit of mol. wt 300,000 was located for all (six) strains of C. pylori subjected to SDS-PAGE whereas St1 had two active forms of mol. wts 140,000 and 150,000. Western-blot analysis indicated the presence of anti-urease antibodies in the sera of patients with C. pylori-associated gastritis. The response to C. pylori urease was not strain-specific but no cross-reactivity was detected between the C. pylori enzyme and that of St1. The very high urease activity of these bacteria is likely to be important in colonisation of the host. Possession of glutamate dehydrogenase activity by both organisms suggests that one role of the urease may be to assimilate the available urea nitrogen. Modification of the local environment to facilitate long-term colonisation is another possible function. Protection from acid is unlikely to be a primary role as the natural habitat of the organism St1 is the non-acid-secreting tissue of the small intestine.
J Med Microbiol 1988 Sep
PMID:The urease enzymes of Campylobacter pylori and a related bacterium. 317 69

Phycoerythrin, ferritin, urease, beta-galactosidase and thyroglobulin, with molecular masses in excess of 200 kDa, adsorb and consequently fail to migrate to, and focus at, their pI positions in electrofocusing in immobilized pH gradients at a total Immobiline concentration of 20 mM while they do focus normally in pH gradients formed by carrier ampholytes. The addition of carrier ampholytes (pH range 3.5-9.5) at concentrations of 0.1 to 5% to the Immobiline-containing gels reduces adsorption (desorbs) some but not all of the 5 proteins at specific Immobiline concentrations. The adsorption is not due to water redistribution and consequent reduction in gel porosity; nor is it due to conductivity minima across the pH gradient. The hypothesis that the presence of oligomeric Immobiline contributed to the protein adsorption is the subject of the accompanying report.
Electrophoresis 1988 Sep
PMID:The adsorption of large proteins in electrofocusing on immobilized pH gradients: I. Protein specificity and dependence on Immobiline and carrier ampholyte concentrations. 324 43

The Syva EMIT Autolab 6000 and the Abbott TDX automated methods for measuring serum aminoglycoside concentrations were compared with each other and with a new semiautomated version of the urease technique. Each was evaluated for accuracy, reproducibility, cost, and ease of use. All three methods gave satisfactory results, although the Abbott TDX was the most accurate. Both automated methods gave results within minutes, whereas the new urease method, which involved more initial manipulation, took 1.25 h to complete (mainly incubation time). There was no difference in accuracy of performance between experienced and inexperienced operators. The new urease method was much cheaper in terms of initial capital expenditure and in cost per test and needed no provision of manufacturer's back-up maintenance services. This could prove invaluable in situations where financial resources are at a premium. Otherwise, the Abbott TDX is currently our method of choice, and reasons for its preference to the EMIT system are listed.
J Clin Microbiol 1987 Sep
PMID:Comparative analysis of two rapid automated methods and a semiautomated version of the urease method for determining aminoglycoside concentrations in serum. 330 45

Twelve strains of Campylobacter pyloridis isolated in the antrum and/or fundus in 8 patients were analyzed for antibiotype. The results obtained, compared with those in the literature, enabled assessment of the culture media which are the best adapted for isolation, the main criteria for identification (urease, alkaline phosphatase, nitratereductase, growth temperature), their sensitivities (beta-lactamines, tetracyclines, macrolides) or their resistance to antibiotics (colistin, vancomycin, co-trimoxazole, nalidixic acid).
Pathol Biol (Paris) 1987 Sep
PMID:[Campylobacter pyloridis: bacteriological study and sensitivity to antibiotics]. 331 11

Analysis by SDS-PAGE of Ureaplasma urealyticum (predominantly serotype 8), propagated in a growth medium containing 10% (v/v) foetal calf serum, revealed a complex series of polypeptides apparently free of medium contaminants. Serological analysis using an immobilized antibody reagent, and immunoblotting using a polyclonal serum, showed the presence of two major and several minor antigens. One major antigen, a putative surface component of apparent molecular mass 96 kDa was shown, with a monoclonal antibody, to be serotype-specific. Growth of the organism was partially suppressed in the presence of the antibody. The second major antigen had an apparent molecular mass of 76 kDa and was presumed to be an internal component since it failed to label with the Bolton and Hunter reagent, in contrast to the 96 kDa antigen. Another monoclonal antibody was characterized which detected the canonical urease enzyme of the organism serotype 8 and of the two other human serotypes tested. Purification of this urease antigen by affinity chromatography and electrophoretic analysis of polypeptides after denaturation revealed a single polypeptide of molecular mass 76 kDa, putatively related to the above major antigen. Enzymic activity could be recovered after purification and demonstrated by in situ techniques only when electrophoretic analysis was done under non-denaturing conditions suggesting that the functional enzyme is a multimeric complex.
J Gen Microbiol 1987 Sep
PMID:Preliminary characterization of the urease and a 96 kDa surface-expressed polypeptide of Ureaplasma urealyticum. 344 56

One hundred and forty seven isolates of Serratia marcescens were collected from diverse clinical and environmental sources in south-east Texas. Natural isolates were compared with hospital strains for the occurrence of 12 potential virulence determinants. Their overall frequency was as follows: haemolytic activity 48%; lecithinase 95%; lipase 95%; motility 99%; pigmentation 24%; plasmid carriage 46%; proteolytic activity 98%; siderophore activity 99%; urease activity 5%; mannose-sensitive haemagglutination 96%; mannose-resistant haemagglutination 61%; and mannose-resistant type-K haemagglutination (MR/K-HA) 68%. Clinical strains demonstrated a significantly higher occurrence of MR/K-HA (p less than 0.001) and non-pigmentation (p less than 0.01) than environmental isolates.
J Med Microbiol 1986 Sep
PMID:A survey of potential virulence factors in clinical and environmental isolates of Serratia marcescens. 352 99


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