Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.4.17 (adenosine deaminase)
 5,206 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The enzymatic inosine 5'-monophosphate assay described by Grassl [in, Methods of Enzymatic Analysis (H. U. Bergman, ed.), pp. 2168-2171, Academic Press, New York (1974)] is highly nonspecific, as ITP, ATP, ADP, AMP, and adenosine react stoichiometrically. The reactivity with the adenine derivatives is due to the tri- and diphosphatase activity of alkaline phosphatase (AP), coupled with adenosine deaminase (and possibly AMP deaminase) contamination of commercially available preparations of AP, purine-nucleoside phosphorylase, and/or xanthine oxidase. The inclusion of coformycin (0.05 microgram/ml), a potent inhibitor of these deaminases, completely eliminated the cross-reactivity. ITP, however, still reacted stoichiometrically due to the tri- and diphosphatase activity of AP. Meyer and Terjung [Amer. J. Physiol. 237 C111-C118 (1979)] introduced a modification of Grassl's procedure, substituting 5'-nucleotidase for AP. It has been found that this disallows reactivity with ATP, ADP, and ITP but that AMP and adenosine still react completely. Coformycin prevents this cross-reactivity. It is therefore recommended that the assay be carried out with 5'-nucleotidase (instead of AP) and coformycin, in order to achieve a more specific assay, and one more suitable for use with whole tissue extracts.
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PMID:An enzymatic inosine 5'-monophosphate assay of increased specificity. 298 81

The activity of 5'-nucleotidase, AMP deaminase, adenosine deaminase, acid phosphatase, alkaline phosphatase and nucleotide pyrophosphatase was assayed in human thyroid glands. The 5'-nucleotidase activity was higher than that of AMP deaminase which suggested that AMP undergoes degradation primarily as a result of dephosphorylation in thyroid tissue. A high acid phosphatase activity was noted as compared to that of alkaline phosphatase activity. In toxic goitre the increase in adenosine deaminase and acid phosphatase was observed together with the decrease in pyrophosphatase activity.
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PMID:Activity of 5'-nucleotidase, AMP deaminase, adenosine deaminase, acid and alkaline phosphatase and nucleotide pyrophosphatase in human thyroid. 300 51

The rat brains homogenized with different media (sucrose, ethylene glycol, dimethyl sulfoxide and urea) yielded different amounts of microsomal fractions. The dielectric constant, density and viscosity of the homogenization media did not correlate with the amount of microsomes separated by differential centrifugation. The homogenization media containing dimethyl sulfoxide were the most efficient for the isolation of rat brain microsomes. The increase in the yield was up to 4-fold when 50% (v/v) dimethyl sulfoxide was employed. Microsomes isolated in this manner were analogous to those obtained from isotonic sucrose solution, as was demonstrated by their chemical and enzymatic (5'-nucleotidase, adenosine deaminase, guanine deaminase, purine-nucleoside phosphorylase, lactate, malate and glutamate dehydrogenases, amine oxidase fumarate hydratase, acid and alkaline phosphatase, acetylcholinesterase, NADPH-cytochrome c reductase, catalase and thiamine-diphosphatase) characterization.
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PMID:An improved method for the preparation of rat brain microsomes. 371 74

To evaluate the effect of aging upon the small intestine, the distribution, content, and concentration of epithelial cell enzymes at different levels along the crypt-villus column were measured in aging and young adult, male, Fisher 344 rats. Specific activities of sucrase, maltase, lactase, and adenosine deaminase in mucosal homogenates were lower in the upper intestines of aging than in young animals, whereas the specific activity and content of thymidine kinase was higher. Enzyme activities were measured in cells obtained by cryostat sectioning from villus tip to crypt base. Sucrase and maltase activities were fully expressed nearest the crypt, alkaline phosphatase in cells higher on the villus, and adenosine deaminase higher still, whereas thymidine kinase activity was limited to the crypts. The ordered pattern of enzyme expression was maintained in aging rats but the initiation and duration were delayed. Because peak specific enzyme activities were similar in young and aging animals, the reduced specific activities in mucosal homogenates from aging animals were due to an increase in the proportion of relatively undifferentiated villus epithelial cells. These findings are of importance in explaining altered intestinal function during aging without a concomitant change in intestinal structure.
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PMID:Delayed enzyme expression: a defect of aging rat gut. 393 Mar 40

We applied a simple lead salt-based stain for interstitial and vascular 5'-nucleotidase to 150 muscle biopsy specimens. No reaction was obtained with 2'- or 3'-adenosine monophosphate, indicating that the stain was specific, and distinct from phosphatases. Staining was not inhibited by alpha, beta-methylene adenosine 5'-diphosphate, but was prevented by formaldehyde fixation or by brief immersion in octoxynol 9 (Triton X-100). Nucleotidase stains the following specific histologic sites that distinguish it from alkaline phosphatase: the intima and adventitia of medium-sized and large arteries, perineural and muscle spindle sheaths, and tendon insertions. Aside from these structures, normal muscle shows little reaction, as the sarcoplasm and sarcolemma do not stain. Neither of these enzymes shows a compensatory increase, histochemically, in myo-adenylate deaminase deficiency. In Duchenne's muscular dystrophy, however, and particularly in inflammatory myopathy, interstitial staining of 5'-nucleotidase is increased, leading to investment of most muscle fibers in the affected area. The stain rarely identifies regenerating fibers. Although alkaline phosphatase commonly shows a corresponding increase in interstitial staining, we encountered six cases of inflammatory myopathy in which this was absent, despite pronounced endomysial staining in the 5'-nucleotidase reaction. 5'-Nucleotidase thus appears to provide a valuable adjunct in the diagnosis of inflammatory myopathy.
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PMID:Interstitial 5'-nucleotidase stain for frozen biopsy specimens of skeletal muscle. A useful adjunct in the diagnosis of polymyositis. 619 1

The ribose-modified chromophoric and fluorescent analog of ATP 2',3'-O-(2,4,6-trinitrocyclohexadienylidene) adenosine 5'-triphosphate (TNP-ATP) has been synthesized previously (Hiratsuka, T., and Uchida, K. (1973) Biochim. Biophys. Acta 320, 635-647 and Hiratsuka, T. (1976) Biochim. Biophys. Acta 453, 293-297). In the present study, four TNP-derivatives of ATP, ADP, AMP and adenosine were synthesized and compared for several chemical, spectral and enzymatic properties. Their visible absorption and fluorescent properties were found to be quite similar. Visible absorption and fluorescence spectra of TNP-derivatives were sensitive to solvent polarity. TNP-adenosine and TNP-AMP showed considerable substrate activities with adenosine deaminase and alkaline phosphatase, respectively. TNP-ATP proved to be an excellent substitute for ATP in adenylate kinase and myosin ATPase systems. The results indicate that these analogs are useful as chromophoric and fluorescent probes for hydrophobic regions in adenine nucleoside and nucleotide requiring enzymes.
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PMID:Biological activities and spectroscopic properties of chromophoric and fluorescent analogs of adenine nucleoside and nucleotides, 2',3'-O-(2,4,6-trinitrocyclohexadienylidene) adenosine derivatives. 629 7

Ten enzymes, all known to be glycoproteins, were examined by electrophoresis or gel isoelectric focusing in 12 different patients with primary or secondary sialidase deficiency. Aberrant electrophoretic mobilities of many of the enzymes attributable to abnormal sialylation were found in all the patients. In ten of the patients seven of the enzymes were affected. The unaffected enzymes were beta-galactosidase, alkaline phosphatase and beta-glucuronidase. In the cells from the two patients with I cell disease (mucolipidosis II) in which sialidase is one of many deficient enzymes, beta-galactosidase, alpha-galactosidase, alpha-fucosidase and alpha-mannosidase were undetectable, alkaline phosphatase showed a normal electrophoretic mobility and acid phosphatase, adenosine deaminase, alpha-glucosidase and beta-D-N-acetylhexosaminidase showed aberrant mobilities.
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PMID:Electrophoretic analysis of glycoprotein enzymes in the sialidoses and mucolipidoses. 645 53

The present work describes an assay which is highly specific for ribose-5-phosphate. The method is based on the following three-stage enzymatic conversion: (1) ribose 5-phosphate in equilibrium ribose 1-phosphate (phosphopentomutase); (2) ribose 1-phosphate + adenine in equilibrium adenosine + Pi (adenosine phosphorylase); (3) adenosine + H2O----inosine + NH3 (adenosine deaminase). Ribose 5-phosphate may be determined either directly following the change in absorbance at 265 nm associated with the conversion of adenine to inosine, or radioenzymatically by measuring the radioactivity of inosine formed from [8-14C]adenine, after chromatographic separation of the nucleoside on polyethyleneimine-cellulose. The spectrophotometric assay was used to follow ribose 5-phosphate formation and ribose 1-phosphate consumption catalyzed by phosphopentomutase. Further, the ability of alkaline phosphatase, 5'-nucleotidase and crude extract of Bacillus cereus cells to act on ribose 5-phosphate was tested. The radioenzymatic assay was proved useful in determining the levels of ribose 5-phosphate in rat tissues.
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PMID:Spectrophotometric and radioenzymatic determination of ribose-5-phosphate. 653 May 7

Eight 5'-(steroid-21-phosphoryl)-9-(beta-D-arabinofuranosyl)-adenines (IV-XI) have been prepared and evaluated against L1210 lymphoid leukemia in culture. These include the 9-(beta-D-arabinofuranosyl)adenine conjugates of hydrocortisone (IV), cortisone (V), corticosterone (VI), cortexolone (VII), 11-deoxycorticosterone (VIII), prednisolone (IX), prednisone (X), and dexamethasone (XI). Conjugates IV, IX, X, and XI inhibited the in vitro growth of L1210 lymphoid leukemia cells by 50% (ED50) at a concentration of 2.3-7.8 microM, while 9-(beta-D-arabinofuranosyl)adenine (vidarabine, I) and its 5'-monophosphate (II) each showed ED50 value of 30 microM. All of the conjugates were enzymatically hydrolyzed to the corresponding steroid and II, the latter undergoing further hydrolysis to I, by phosphodiesterase I, 5'-nucleotidase, and acid phosphatase. However, these conjugates were resistant to hydrolysis by alkaline phosphatase and adenosine deaminase.
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PMID:Nucleoside conjugates V: Synthesis and biological activity of 9-(beta-D-arabinofuranosyl)adenine conjugates of corticosteroids. 670 3

Changes in oxidative metabolism were studied in hepatopancreas, muscle, and hemolymph of the edible crab Scylla serrata, exposed to a sublethal concentration (2.5 ppm) of cadmium chloride. A significant decrease in glycogen, total carbohydrates, and pyruvate and an increase in lactate levels in hepatopancreas and muscle were observed. Hemolymph sugar levels were increased in experimental crabs. An increase in phosphorylase suggested increased glycogenolysis during cadmium toxicity. The decrease in lactate dehydrogenase activity and the increase in lactate content indicated reduced mobilization of pyruvate into the citric acid cycle. Krebs cycle enzymes such as succinate dehydrogenase and malate dehydrogenase were found to be decreased, suggesting impairment of mitochondrial oxidative metabolism as a consequence of cadmium toxicity. Glucose-6-phosphate dehydrogenase activity was increased, suggesting enhanced oxidation of glucose by the HMP pathway. Cytochrome-c oxidase and Mg2+ ATPase activity levels decreased, indicating impaired energy synthesis during cadmium stress. Acid and alkaline phosphatase activities increased, suggesting enhanced breakdown of phosphates to release energy in view of impaired ATPase system during cadmium exposure. A significant decrease in protein and free amino acid and an increase in ammonia, urea, and glutamine levels were observed in the tissues during exposure. An increase in protease, alanine aminotransaminase, and aspartate aminotransaminase suggested increased proteolysis and transamination of amino acids. The increase in glutamate dehydrogenase, AMP deaminase, and adenosine deaminase indicated increased ammonia production. The increased arginase and glutamine synthetase suggested the detoxification or mobilization of ammonia toward the production of urea and glutamine. These results suggest that cadmium affects oxidative metabolism and induces hyperammonemia, and crabs switch over their metabolic profiles toward compensatory mechanisms for the survivability in cadmium-polluted habitats.
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PMID:Changes in oxidative metabolism in selected tissues of the crab (Scylla serrata) in response to cadmium toxicity. 753 86


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