Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Golgi-rich fraction was isolated from Harding-Passey mouse melanoma by centrifugation through the discontinuous sucrose density gradient and its properties were compared with those of the same fraction isolated from rat liver. The specific activity of UDP-galactose: N-acetylglucosamine galactosyltransferase was 35 times higher in the melanoma Golgi fraction than in the melanoma homogenate and was a half that in the rat liver Golgi fraction. The specific activities of marker enzymes for other subcellular components such as 5'-nucleotidase, acid phosphatase and glucose-6-phosphatase in the melanoma Golgi fraction were all one-third those in the melanoma homogenate. Electron micrographs of the negatively-stained Golgi fractions of melanoma and liver revealed the presence of a system of tubules, vesicles and plate-like center regions which are known as components of Golgi apparatus. Tyrosinase activity was found to be present in this fraction of mouse melanoma, but its specific activity was lower than that in the rough or smooth surface membrane fraction or in the melanosome fraction.
Tohoku J Exp Med 1978 Sep
PMID:Isolation and characterization of a Golgi-rich fraction from the Harding-Passey mouse melanoma. 10 Aug 98

Differential centrifugation was applied to adult and foetal liver of monkey. Obtained fractions were: F1 (800 X g); F2 (12 500 X g); F3 (200 000 X g); and cell sap. Analysis of chemical compounds of these fractions shows that: (1) adult and foetal nucleic acids levels are similar; (2) there are more proteins in adult than in foetal hepatocytes; (3) most of the glycogen is located in F3; the foetal level is twenty times higher than the adult level. Plasma membrane enzymes (5'-nucleotidase, adenylate cyclase) show a nucleomicrosomic distribution. The distribution of alkaline phosphatase is not significant. Mitochondrial enzymes (monoamine oxydase, succinate cytochrome c reductase, cytochrome oxydase) are enriched in F2 without any sedimentation in F3. There is more malate dehydrogenase liberated in cell sap during foetal liver fractionation. This indicates the foetal mitochondria are more sensitive to the homogenisation method. Lysosomal enzymes (acid phosphatase, N-acetylglucosaminidase) are enriched in F2. The same observation for N-acetylglucosaminidase as for malate dehydrogenase leads to the same conclusion for foetal lysosomes. Endoplasmic reticulum and Golgi enzymes (glucose-6-phosphatase and related phosphotransferase activity, NADPH-cytochrome c reductase and sialytransferase) are much enriched in F3. Thus this fraction F3 is pure enough to allow the observation of the modification produced on endoplasmic reticulum and Golgi apparatus during foetal and neonatal development.
Biochim Biophys Acta 1979 Sep 20
PMID:[Comparative study of microsomal enzymic activities in adult and foetal monkey hepatocytes (author's transl)]. 11 30

A pronounced effect of concanavalin A (Con A) upon activity of ecto-5'-nucleotidase of intact C6 glioma cells in culture has been demonstrated. A near linear rate of decrease in 5'-nucleotidase activity was observed upon treatment with concentrations of Con A up to 0.25 muM. Nonspecific phosphatase activity and Ca2+-dependent ATPase activity were not inhibited by Con A treatment of the cells. Of the total 5'-nucleotidase activity of C6 cells (Vmax = 5.0 mumol of Pi liberated/mg of cell protein/hour), approximately 20% still remained after treatment with high concentrations of Con A. The inhibitory effect of Con A operated to reduce substantially Vmax for ecto-5'-nucleotidase. Inhibition was reversed by briefly incubating the Con A-treated cells with alpha-methyl-D-glucoside, or alpha-methyl-D-mannoside, the later being more effective. These findings suggest that a relatively specific, reversible, inhibition of ecto-5'-nucleotidase results from Con A binding to the surface of the intact cultured mammalian cells.
J Biol Chem 1975 Sep 10
PMID:Concanavalin A inhibition of ecto-5'-nucleotidase of intact cultured C6 glioma cells. 12 59

The influence of the mode of preparation upon some of the characteristics of white adipose tissue plasma membranes and microsomes has been reported. Plasma membrane fractions prepared from mitochondrial pellet were shown to have higher specific activities of (Mg2+ + Na+ + K+)-ATPase than plasma membranes originating in crude microsomes. Isolation of fat cells by collagenase treatment was found to result in a decrease in specific activity of the plasma membrane enzymes; in plasma membranes prepared from isolated fat cells, the specific activity values obtained for (Mg2+ + Na+ +k+)-ATPase and 5'-nucleotidase were only 42% and 6.3% respectively of those obtained in plasma membranes prepared from whole adipose tissue. Purification of whole adipose tissue crude microsomes by hypotonic treatment caused extensive solubilization of the endoplasmic reticulum marker enzymes, NADH oxidase and NADPH cytochrome c reductase. The lability of endoplasmic reticulum marker enzymes, however, was found to be greatly diminished in the preparations from isolated fat cells. The possibility that NADH oxidase and NADPH cytochrome c reductase activities found in the plasma membranes are microsomal enzymes adsorbed by the plasma membranes is discussed. The peptide patterns as well as the NADH oxidase and NADPH cytochrome c reductase activity patterns of plasma membranes and purified microsomes were compared by means of sodium dodecyl sulfate or Triton X-100 polyacrylamide gel electrophoresis.
Biochim Biophys Acta 1975 Sep 16
PMID:Comparison of plasma membranes and endoplasmic reticulum fractions obtained from whole white adipose tissue and isolated adipocytes. 12 89

Pancreas of the cat was fractionated into its subcellular components by centrifugation through an exponential ficoll-sucrose density gradient in a zonal rotor. This enables a preparation of four fractions enriched in plasma membranes, endoplasmic reticulum, mitochondria and zymogen granules, respectively. The first fraction, enriched by 9- to 15-fold in the plasma membrane marker enzymes, hormone-stimulated adenylate cyclase, (Na+K+)-ATPase, and 5'-nucleotidase, is contaminated by membranes derived from endoplasmic reticulum but is virtually free from mitochondrial and zymogen-granule contamination. The second fraction from the zonal gradient shows only moderate enrichment of the above marker enzymes but contains a considerable quantity of plasma membrane marker enzymes and represents mostly rough endoplasmic reticulum. The third fraction contains the bulk of mitochondria and the fourth mainly zymogen granules as assessed by electron microscopy and marker enzymes for both mitochondria and zymogen granules, namely succinic dehydrogenase, trypsin and amylase. Further purification of the plasma membrane fractions by differential and sucrose step-gradient centrifugation yields plasma membranes enriched 40-fold in basal and hormone-stimulated adenylate cyclase and (Na+K+)-ATPase.
J Membr Biol 1977 Sep 14
PMID:Studies on isolated subcellular components of cat pancreas. I. Isolation and enzymatic characterization. 14 36

Distinct morphological regions, initial, middle and terminal segments, were distinguishable histologically; the middle segment was further subdivided into proximal, intermediated and distal parts. PAS-positive, diastase-resistant reaction was detected in the blood vessels, subepithelial tissue and stereocilia of all segments. Acid phosphatase was demonstrated in the epithelial cells with the highest activity being in the proximal part of the middle segment. Non-specific esterase gave a similar reaction but the strongest activity was in the terminal segment. Alkaline phosphatase, adenosine triphosphatase and adenosine monophosphatase were of similar activity in the subepithelial tissue, blood vessels, stereocilia and luminal contents; the strongest reaction occurred in the middle segment. Lactate, succinate, glutamate and glucose-6-phosphate dehydrogenases were examined; LDH was more active than the others particularly in the terminal segment. Some reaction was found in the epithelial cells, subepithelial tissue and luminal contents.
J Reprod Fertil 1979 Sep
PMID:On the regional histology and histochemistry of the epididymis of the camel (Camelus dromedarius). 15 47

Enzyme distribution profiles of clarified bovine mammary homogenates separated by equilibrium centrifugation on linear sucrose gradients suggested that several of the commonly utilized marker enzymes for rat liver are also valid markers for mammary cellular components. These marker enzymes include: Succinate dehydrogenase (mitochondria), nicotinamide adenine dinucleotide phosphate cytochrome c reductase and, to a lesser extent, retenone insensitive nicotinamide adenine dinucleotide cytochrome c reductase (endoplasmic reticulum), galactosyl transferase (Golgi apparatus), 5'-nucleotidase (plasma membranes), uric acid oxidase (microbodies), and acid phosphatase (lysosomes). Rotenone sensitive nicotinamide adenine dinucleotide cytochrome c reductase and sodium, potassium, magnesium-stimulated adenosine triphosphatase were widely distributed among subcellular fractions and are not valid marker enzymes. The boyant densities determined for the above fractions should aid in design of methods to obtain enriched sources of these components for analysis.
J Dairy Sci 1975 Sep
PMID:Membranes of mammary gland. XI. Marker enzyme distribution profiles for membranous components from bovine mammary gland. 17 Dec 90

A rat liver nuclear envelope fraction isolated essentially by the technique of Monneron et al. (J. Cell Biol. 55, 104-125 (1972) is characterized by high levels of glucose-6-phosphatase and 5'-nucleotidase. A broadly specific nucleoside triphosphatase activity is present. Cytochromes b5 and P-450 as well as NADPH- and NADH-cytochrome c reductase activities are present but at lower levels than found in microsomes. Cytochrome c oxidase activity is low. RNA polymerase activity is absent from the nuclear envelope fraction. Cytochemistry shows that glucose-6-phosphatase activity is strong and restricted to the nuclear envelope of nuclei. 5'-Nucleotidase shows weak reaction deposit in whole nuclei but in contrast gives clear reaction deposit in isolated nuclear envelopes. Cytochemical reaction deposit due to nucleoside triphosphatase activity is not restricted to the nuclear envelope but is found to a larger extent within the nucleus.
Biochim Biophys Acta 1976 Sep 21
PMID:An enzymic analysis of a nuclear envelope fraction. 18 34

1. Cortisol treatment of rabbit foetuses in utero at 24 days gestation produced a significant decrease in the lung-weight to body-weight ratio compared with littermate controls by day 26. Histological examination revealed that the alveoli of the treated lungs were more open, the walls were thinner and the osmiophilic bodies were more numerous. 2. Cortisol treatment as described above produced significant increases (P<0.05) in the rates of incorporation of [(14)C]choline into phosphatidylcholine and of [(14)C]ethanolamine into phosphatidylethanolamine in vitro compared with littermate controls. This indicates that glucocorticoids produce an overall increase in phospholipid metabolism rather than a specific increase in phosphatidylcholine production. 3. The addition of 1,2-diacyl-sn-glycerols from egg phosphatidylcholine produced a 10-fold increase in the activity of choline phosphotransferase and a 3-fold increase in the activity of ethanolamine phosphotransferase in rabbit lung homogenates. The addition of 1,2-dipalmitoyl-sn-glycerol did not affect these activities. These results demonstrate that in the presence of exogenous 1,2-dipalmitoyl-sn-glycerol, the activities of these enzymes are dependent on the presence of endogenous 1,2-diacylglycerols. 4. Cortisol administration had no significant effect on the activity of choline phosphotransferase or ethanolamine phosphotransferase with endogenous or exogenously added diacylglycerols. The activities of other endoplasmic-reticulum enzymes (sn-glycerol 3-phosphate phosphatidyltransferase, sn-glycerol 3-phosphate acyltransferase and NADPH-cytochrome c reductase) were not significantly altered by the hormone administration. Oestrone sulphate sulphohydrolase activity was significantly decreased (P<0.05) by cortisol injection, but this effect varied with the foetuses from different does. 5. Cortisol administration had no effect on the activities of mitochondrial (monoamine oxidase, succinate dehydrogenase), plasma-membrane (5'-nucleotidase) or lysosomal (acid phosphatase, N-acetyl-beta-d-glucosaminidase) enzymes. The activity of membrane-associated phosphatidate phosphohydrolase, an enzyme associated with the osmiophilic granules of the type-II alveolar cells, was increased in the lungs of treated foetuses, but the difference was not significant (0.10>P>0.05).
Biochem J 1977 Sep 15
PMID:Cortisol induction of pulmonary maturation in the rabbit foetus. Its effects on enzymes related to phospholipid biosynthesis and on marker enzymes for subcellular organelles. 20 47

Gentle homogenization followed by differential and density gradient centrifugation was used to purify line 10 and line 1 guinea pig hepatoma plasma membranes in the form of ghosts. Yields of 15--25% allowed enough membranes to be obtained from a single ascites tumor-bearing animal for immunologic and biochemical studies. Although the plasma membrane marker enzyme (Na+ + k+)atpase was present in normal concentrations in both line 10 and line 1 hepatomas, 5'-nucleotidase was reduced over 100-fold in both tumors and phosphodiesterase I was increased 210-fold in the line 10 hepatomas.
J Natl Cancer Inst 1978 Sep
PMID:Preparation of plasma membranes from line 10 and line 1 guinea pig hepatomas. 21 Dec 44


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