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)

Certain tRNAs in S. cerevisiae (tRNATyr and tRNAPhe) arise via precursor molecules which are mature at the 5' and 3' termini but contain intervening sequences adjacent to the anticodon (Knapp et al., 1978; O'Farrell et al., 1978). In addition to these molecules, precursors to several other tRNAs accumulate in a temperature-sensitive mutant (ts136) at the nonpermissive temperature. We have analyzed one of these species and shown that it is a precursor to a minor species of tRNASer. This precursor is also mature at both termini and contains an intervening sequence of 19 nucleotides adjacent to the hypermodified A residue 3' to the anticodon. The sequence can be arranged in a secondary structure in which the anticodon stem is extended by additional base-pairing, and contains the sites of excision and ligation within two looped regions. Support for this structure was provided by analysis of the products of limited digestion with RNAase T1. recently Piper (1978) reported the isolation of a minor species of tRNASer which decodes UCG. He found this species to be structurally heterogeneous and determined that the less abundant form corresponds to the tRNA which is altered in the recessive lethal SUP-RL1 amber suppressor. Our data now suggest that the more abundant form may be restricted to reading UCA in vivo; thus mutation of the minor species would result in complete loss of UCG-decoding ability and explain the recessive lethality of SUP-RL1. We have shown that the precursor which accumulates in ts136 corresponds exclusively to this minor tRNASerUCG species. Our results suggest that this may be the only gene for tRNASer in yeast which contains an intervening sequence.
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PMID:A precursor to a minor species of yeast tRNASer contains an intervening sequence. 38 30

A total of 387 yeasts from the contents of the digestive tracts of domestic animals and poultry were identified by slide agglutination tests using factor antisera and urease tests. The results of this serological test were very satisfactory with respect to accuracy and rapidity, particularly when performed in combination with concomitant physiological tests only for assimilation of inositol and potassium nitrate. It may be concluded that such a combination of serological and biological tests is very useful for identifying yeast strains from various sources.
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PMID:Rapid identification of yeasts by serological methods: a combined serological and biological method. 39 60

We have attended to a comparative research between two commercial microsystems: Enterotube and Minitek in order identify the Enterobacteriaceae and a reference system given by the combination of the usual macromethods already used in our laboratory. We have examined 401 bacterial cultures of Gram bacillus which we trought to belong to Enterobacteriums, coming from clinical material (excrements, urine, pharyngeal swabs, vaginal swabs, urethral swabs and espectoration) we have received for the bacteriological diagnosis. 390 of 401 cultures have shown to be Enterobacteriums. The biochemical reactions they have given show that the Enterotube and the Minitek have, with the usual system a good accordance for the following tests: dextrose (acid and gaz) lysin and ornithine decarboxylase, production of H2S and indole, phenylalanine deaminase and urease; while we have some statistically significant discordances for the fermenting of lactose and the use of citrate. We have also significant discordances E/C for the fermenting of dulcitole while the ones of Minitek are acceptables. The notes recommend the use, in the specialized bacteriological laboratories, of the conventional tests.
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PMID:[Evaluation of two miniaturized systems widely used in the laboratories for the identification of the "Enterobacteriaceae" (author's transl)]. 39 48

The possibility to keep some biochemical reactions of the parent strains (urease-positive, glucose fermentation, phenylalanine-deaminase-positive, H2S but not indol production) was demonstrated in 5 L-forms, obtained from as many strains of Pr. mirabilis and in 1 L-form, isolated from a vaginal secretion and identified as belonging to the same species. The indirect hemagglutination technique, made by the sonicated antigen in 3 of the 6 L-forms with Proteus OXK antiserum, resulted positive in titers varying from 1:128 to 1:1024. Crossed tests made with antisera for different bacterial species (e. coli, Shigella, klebsiella, ecc.) and of Mycoplasma (M. hominis, M. orale, M. salivarium, M. fermentans, M. arthritidis) put in evidence aspecific reactions only in 1.3% of the bacterial antisera. On the contrary, all 5 antisera for Mycoplasma were able to agglutinate the sensitized erythrocytes at titers quite analogous to that of the homologous antiserum. The sensitivities to various antibiotics of the 6 L-forms and the parent strains has been determined. All of L-forms were more resistent to the tetracycline than L-forms of other bacterial species. On the basis of te results got by biochemical and serological tests, we confirm the necessity to make use of both the groups of tests, in order to identify the L-forms of recent isolation.
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PMID:[Researches on some biochemical and serological properties and on the sensitivity to antibiotics of L-forms of "Proteus" (author's transl)]. 40 87

Papain (EC 3.4.22.2) has been coupled to supports of titanium (IV) oxide and cellulose, which are particulate and pre-coated with diazotised 1,3-diaminobenzene, giving water-insoluble and stable derivatives which possess low proteolytic activity but high esterolytic activity. In addition the reversible binding of zinc (II) at the active site of papain has been exploited to inhibit protectively the enzyme during its linkage to the aforementioned supports, thereby yielding water-insoluble derivatives of papain having superior activity upon reactivation with EDTA. Application of the improved procedure of enzyme coupling to macroporous cellulose particles gave a water-insoluble derivative of papain having further enhanced proteolytic activity. Other properties of the water-insoluble derivatives of papain and of similarly prepared water-insoluble conjugates of urease (EC 3.5.1.5) and cholinesterase (EC 3.1.1.8) with cellulose are also reported.
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PMID:Active water-insoluble derivatives of papain and other enzymes based on preformed diazonium-type supports. 40 36

Pseudomonas aeruginosa AI 3 was able to grow in medium containing acetanilide (N-phenylacetamide) as a carbon source when NH4+ was the nitrogen source but not when urea was the nitrogen source. AIU mutants isolated from strain AI 3 grew on either medium. Urease levels in bacteria grown in the presence of urea were 10-fold lower when NH4+ or acetanilide was also in the medium, but there were no apparent differences in urease or its synthesis between strain AI 3 and mutant AIU 1N. The first metabolic step in the acetanilide utlization is catalyzed by an amidase. Amidases in several AIU strains showed altered physiochemical properties. Urea inhibited amidase in a time-dependent reaction, but the rates of the inhibitory reaction with amidases from the AIU mutants were slower than with AI 3 amidase. The purified amidase from AIU 1N showed a marked difference in its pH/activity profile from that obtained with purified AI 3 amidase. These observations indicate that the ability of strain AIU 1N and the other mutants to grow on acetanilide/urea medium is associated with a mutation in the amidase structural gene; this was confirmed for strain AIU 1N by transduction.
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PMID:Pseudomonas aeruginosa mutants resistant to urea inhibition of growth on acetanilide. 41 Jul 88

The isolation, characterization, and identification of a microorganism isolated from gastrointestinal tracts of rabbits with mucoid enteritis are described. The isolated organism did not grow on standard media. This organism grew around colonies of Staphylococcus aureus and Lactobacillus desidiosus and around disks saturated with diphosphopyridin nucleotide (factor V) on brain heart infusion agar. The growth of this organism was also observed on media supplemented with beta-nicotinamide adenine dinucleotide. The organism appeared as gram-negative, pleomorphic rods or coccobacilli. It was positive for urease, oxidase, catalase, glycosidases, porphyrin, and indole, and it fermented glucose and sucrose. All of these characteristics suggest that the organism is a member of the genus Haemophilus. Because of its isolation from rabbits and differences in some characteristics from other species of this genus, the name Haemophilus paracuniculus is proposed for this organism.
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PMID:Characterization of a Haemophilus paracuniculus isolated from gastrointestinal tracts of rabbits with mucoid enteritis. 42 39

A microencapsulated multienzyme system containing urease, glutamate dehydrogenase and glucose dehydrogenase has been used to convert urea and ammonia into an amino acid. The effect of two different glucose dehydrogenases was studied in detail. High-specific-activity glucose dehydrogenase requires minimal cofactor and glucose and can greatly facilitate the further development of this approach for possible clinical applications.
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PMID:Effects of glucose dehydrogenase in converting urea and ammonia into amino acid using artificial cells. 43 22

A large radiodense calculus in the left renal pelvis of a 22-month-old, male Great Dane disappeared one month following surgical removal of two struvite (magnesium ammonium phosphate) calculi from the right renal pelvis. The dog's urine likely became undersaturated with struvite for a sufficient period to permit dissolution of the renal calculus. Several factors may have contributed to the decrease in urine struvite concentration, including eradication of a urease-producing Proteus sp from the urinary tract and induction of polydipsia and compensatory polyuria by oral administration of sodium chloride.
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PMID:Dissolution of a struvite nephrolith in a dog. 43 42

A novel approach is reported for the removal of ammonium formed from the conversion of urea by urease. By alkalinization, ammonium is converted into free ammonia. Free ammonia can then be very easily removed by a number of approaches: as gaseous ammonia by air bubbling, oxygenator, or air ventilation; by adsorbent for free ammonia; or other approaches.
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PMID:Urea and ammonium removal based on alkalinization and removal of free ammonia. 45 5


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