Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.4 (deaminase)
 5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A bacterium capable of utilizing acetonitrile (methyl cyanide) as the sole source of carbon and nitrogen was isolated from soil and identified as Pseudomonas aeruginosa. This bacterium could also utilize and oxidize numerous lower-mol-wt nitrile compounds and their corresponding amides as growth substrates. A metabolite of acetonitrile in the culture medium was determined to be ammonia. The accumulation of ammonia in the culture medium was proportional to the concentration of the substrate and the inoculum. Cell extracts of the bacterium contained activities corresponding to nitrile aminohydrolase (E C 3.5.5.1) and amidase (E C 3.5.1.4), which regulate the degradation of acetonitrile. Both enzymes were inducible and hydrolyzed a wide range of substrates, and it was determined that the specific activity of amidase was far greater than the activity of nitrile aminohydrolase.
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PMID:Degradation of organic cyanides by Pseudomonas aeruginosa. 192 88

A gram-negative rod-shaped bacterium capable of utilizing acrylonitrile as the sole source of nitrogen was isolated from industrial sewage and identified as Klebsiella pneumoniae. The isolate was capable of utilizing aliphatic nitriles containing 1 to 5 carbon atoms or benzonitrile as the sole source of nitrogen and either acetamide or propionamide as the sole source of both carbon and nitrogen. Gas chromatographic and mass spectral analyses of culture filtrates indicated that K. pneumoniae was capable of hydrolyzing 6.15 mmol of acrylonitrile to 5.15 mmol of acrylamide within 24 h. The acrylamide was hydrolyzed to 1.0 mmol of acrylic acid within 72 h. Another metabolite of acrylonitrile metabolism was ammonia, which reached a maximum concentration of 3.69 mM within 48 h. Nitrile hydratase and amidase, the two hydrolytic enzymes responsible for the sequential metabolism of nitrile compounds, were induced by acrylonitrile. The optimum temperature for nitrile hydratase activity was 55 degrees C and that for amidase was 40 degrees C; both enzymes had pH optima of 8.0.
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PMID:Metabolism of acrylonitrile by Klebsiella pneumoniae. 195 6

The effects of tetronasin on ruminal protein metabolism were investigated in vitro using ruminal fluid from cattle receiving tetronasin in the diet, ovine ruminal fluid from animals not receiving tetronasin and pure cultures of proteolytic ruminal bacteria. Ruminal fluid from cattle receiving tetronasin in a predominantly barley diet had lower proteolytic (76% of control, P less than .10) and deaminative (58% of control, P less than .05) activities than controls after 42 d. The effect of deamination disappeared after 84 d, although the proteolytic activity remained lower (P less than .10) than that of controls. When tetronasin was added in vitro to ruminal fluid from sheep not receiving the ionophore, proteolytic activity (14C-labeled casein hydrolysis) was unaffected, but the rate of ammonia production from amino acids was decreased by 87% (P less than .01). Oligopeptide breakdown was inhibited to a lesser extent (21%, P less than .05). Dipeptidase activity (dialanine hydrolysis) was not affected. The addition of tetronasin to cultures of the ruminal bacteria Ruminobacter amylophilus and Bacteroides ruminicola had no influence on their protease, deaminase or dipeptidase activities. However, when the bacteria were adapted to grow in the presence of tetronasin, deamination of amino acids was severely inhibited (87 to 100%, P less than .01), even when tetronasin was absent from the incubation mixture. Tetronasin had no effect on the proteolytic activity of adapted cultures.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of the ionophore tetronasin on nitrogen metabolism by ruminal microorganisms in vitro. 233 85

Urethane, a cancer-causing chemical, was reported to contaminate alcoholic beverages such as whisky, liquor, wine and sake. Enzymatic removal of urethane would be a possible approach to remove this potentially hazardous chemical from alcoholic beverages. We found that Citrobacter sp. isolated from mouse feces stoichiometrically decomposed urethane to ethanol and ammonia. We named this enzyme "urethanase." Partially purified urethanase could hydrolyze several carbamates and some amides. However, urea, N-alkyl ureas and ethyl esters of organic acids were not hydrolyzed at all. These results suggest that urethanase belongs to the category of amidase. The enzyme was inactive in high concentrations of alcohol and at acidic pH and was practically ineffective for the elimination of urethane from alcoholic beverages.
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PMID:Urethane-hydrolyzing enzyme from Citrobacter sp. 239 57

Acrylamide, a neurotoxic monomer with extensive industrial applications was found to be degraded by the microorganisms present in a tropical garden soil. A bacterium capable of degrading acrylamide was isolated from this soil by enrichment. It was found to be aerobic, gram-negative, motile, short rod and identified as Pseudomonas sp. The bacterium degraded high concentrations of acrylamide (4 g/l) to acrylic acid and ammonia which were utilized as sole carbon and nitrogen source for growth. An amidase was involved in the hydrolysis of acrylamide, which could act on other short chain amides like formamide and acetamide but not on acrylamide analogues: methacrylamide and N,N-methylene bisacrylamide. The enzyme was sensitive to catabolite repression by succinate both in presence as well as absence of nitrogen source.
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PMID:Microbial degradation of acrylamide monomer. 240 64

Porcine calpains (Ca2+-dependent cysteine proteinases) I and II, which had been purified each to a homogeneous state, were found to hydrolyze specifically carboxyl-terminal amide of substance P and several other biologically active peptidyl amides. This amidase-like activity was demonstrated both by determining released ammonia and by separating products on high-performance liquid chromatography followed by amino acid analysis. The calpain-catalyzed deamidation of substance P occurred exclusively at the carboxyl-terminal amide, leaving the side-chain glutamine intact. Enkepharinamide and MSH-release inhibiting factor were scarcely deamidated. Calpains I and II showed similar specificities for these amide substances and similar profiles of inhibitions by various protease inhibitors, but distinctly different Ca2+ requirements. The specificity constants, kcat/Km, for substance P were found to be three to four orders of magnitude higher than those for the synthetic substrates.
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PMID:Amidase-like activity of calpain I and calpain II on substance P and its related peptides. 241 62

Pseudomonas fluorescens NCIB 11764 was capable of utilizing cyanate (OCN-) as a sole nitrogen source for growth. Crude cell extracts from cells grown on cyanate, but not on ammonium sulfate, were induced for an enzyme catalyzing cyanate conversion to ammonia. Enzymatic activity was shown to be bicarbonate dependent and specific for cyanate as a substrate, suggesting that cyanate utilization in this organism is facilitated by an enzyme resembling cyanase (cyanate amidohydrolase; EC 3.5.5.3), as described previously in Escherichia coli and Flavobacterium sp.
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PMID:Cyanase-mediated utilization of cyanate in Pseudomonas fluorescens NCIB 11764. 249 63

Adenosine-5'-monophosphate deaminase is a critical enzyme in the regulation of adenine nucleotide levels in the erythrocyte. The routine examination of this enzyme in crude hemolysates is difficult with the commonly used assay which monitors ammonia generated by the deamination reaction. This report details a radioisotopic assay for AMP deaminase which allows separation of the [14C]inosine 5'-monophosphate product from the [14C]adenosine 5'-monophosphate substrate by ion-exchange chromatography at pH 2.2. The radioisotopic assay is linear with respect to time and enzyme concentration over a considerable range and thereby significantly simplifies the monitoring of crude or dilute enzyme preparations.
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PMID:Radioisotopic assay for erythrocyte adenosine 5'-monophosphate deaminase. 250 31

Cytosine deaminase, encoded by the codA gene in Escherichia coli catalyzes the deamination of cytosine to uracil and ammonia. Regulation of codA expression was studied by determining the level of cytosine deaminase in E. coli K12 grown in various defined media. Addition of either pyrimidine or purine nucleobases to the growth medium caused repressed enzyme levels, whereas growth on a poor nitrogen source such as proline resulted in derepression of cytosine deaminase synthesis. Derepression of codA expression was induced by starvation for either uracil or cytosine nucleotides. Nitrogen control was found to be mediated by the glnLG gene products, and purine repression required a functional purR gene product. Studies with strains harbouring multiple mutations affecting both pyrimidine, purine and nitrogen control revealed that the overall regulation of cytosine deaminase synthesis by the different metabolites is cumulative.
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PMID:Pyrimidine, purine and nitrogen control of cytosine deaminase synthesis in Escherichia coli K 12. Involvement of the glnLG and purR genes in the regulation of codA expression. 267 19

The concentrations of lactate, ammonia and hypoxanthine were determined in blood from the femoral artery, femoral vein and cubital vein under resting conditions in 23 patients with stage II, 10 patients and 20 diabetics with stage IV peripheral arterial occlusive disease (PAOD) and in 19 healthy subjects. The metabolite concentrations were also measured immediately and 20 min after calf exercise in the patients with stage II PAOD and in the controls. At rest, there was a negative arteriovenous difference in femoral lactate level and a positive arteriovenous difference in the ammonia level in all groups. After exercise to the claudication limit, the femoral venous concentration and arteriovenous difference for lactate increased in the patient group significantly higher than in the controls, who were exercised three times as heavily. Furthermore, there was a significant rise in femoral venous ammonia concentration with inversion of the arteriovenous difference into the negative range and an increase in femoral venous hypoxanthine concentration only in the patients with PAOD and not in the controls. A significant correlation was found between the exercise-induced increases in lactate and ammonia. The results indicate activation of the purine nucleotide cycle in the muscles of limbs with impaired circulation, even for a short duration of load. This can be explained by activation of the AMP-deaminase in type I and type IIa muscle fibres by anoxaemia. The purine nucleotide cycle has an emergency metabolic function in ischaemia to maintain muscle contractility. Ammonia determination in femoral blood permits, in association with lactate and hypoxanthine determination, a precise quantitative assessment of the metabolic effects of PAOD.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Influence of peripheral arterial occlusive disease on muscular metabolism. Part 1: Changes in lactate, ammonia, and hypoxanthine concentration in femoral blood. 274 35


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