Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

The objective of this investigation was to find out whether vitamin E deficiency, apart from influencing the lipid component of cellular membranes, also influences the protein component. For that purpose a number of membrane-bound enzymes in the liver of the Pekin duckling were histochemically, cytochemically, and biochemically examined. Furthermore, cells, cellular membranes, and protein particles in membranes were morphometrically investigated. Histochemically five membrane-bound enzymes appeared to be stimulated in vitamin E deficiency: 5'-nucleotidase, glucose-6-phosphatase, isocitrate dehydrogenase (NADP), tetrazolium reductase (NADH), and tetrazolium reductase (NADPH). 5'-Nucleotidase and glucose-6-phosphatase were also investigated cytochemically and biochemically. The cytochemical localization of these enzymes was identical in control and vitamin E-deficient ducklings. Biochemically, a stimulation of these two enzymes also could be demonstrated. The increase per milligram of DNA appeared to be largest whereas the increase per milligram of protein, per milligram of phospholipid, and per milligram of RNA was only half of the increase per milligram of DNA. This can be explained by the 30 per cent increase of the cell volume in vitamin E deficiency leading to an increase of protein, phospholipid, and RNA per cell. The thickness of membranes and the diameter of protein particles in membranes were measured in liver parenchymal cells. In vitamin E deficiency the thickness of the outer mitochondrial membrane and the diameter of protein particles in this membrane were smaller whereas the thickness of the endoplasmic reticular membrane was larger. The increase of the activities of mitochondrial and microsomal enzymes and the decrease of the thickness of the outer mitochondrial membrane and of its protein particles are interpreted to be the result of the influence of free radicals on membranes with electron transport functions. The increase of 5'-nucleotidase activity in the plasma membrane is likely to have a different cause; it may be related to the transport of nucleotides across this membrane.
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PMID:Cellular membranes and membrane-bound enzymes in vitamin E deficiency. A histochemical, cytochemical, biochemical, and morphologic study of the liver of the Pekin duckling. 16 37

Although the preparation of rat liver Golgi apparatus isolated by our method contains appreciable activities of NADH- and NADPH-cytochrome c reductases and glucose-6-phosphatase, these enzymes as well as thiamine pyrophosphatase of the extensively fragmented Golgi fraction are partitioned in aqueous polymer two-phase systems quite differently from those associated with microsomes. Similarly, the partition patterns of acid phosphatase and 5'-nucleotidase of the Golgi fragments differ from those of homogenized lysosomes and plasma membrane, respectively. It is concluded that most, if not all, of these marker enzymes in the Golgi fraction cannot be ascribed to contamination by the non-Golgi organelles. In sucrose density gradient centrifugation the NADH- and NADPH-cytochrome c reductase activities of the Golgi fraction behave identically with galactosyltransferase but differently from the reductase activities of microsomes, again indicating that the reductases are inherently associated with the Golgi apparatus. NADPH-cytochrome c reductase of the Golgi preparation is immunologically identical with that of microsomes. The marker enzymes mentioned above and galactosyltransferase behave differently from one another when the Golgi fragments are subjected to partitioning in aqueous polymer two-phase systems, suggesting that these enzymes are not uniformly distributed in the Golgi apparatus structure.
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PMID:Biochemical studies on rat liver Golgi apparatus. II. Further characterization of isolated Golgi fraction. 20 81

In populations of cultured arterial endothelial and smooth muscle cells grown under the same conditions, we have measured the total activity per cell of 10 enzymes commonly used as "markers" for subcellular organelles: NADH: ferricyanide reductase, NADH:cytochrome c reductase (rotenone insensitive). NADPH:cytochrome c reductase, alpha-glucosidase, 5'-nucleotidase, alkaline phosphodiesterase I, cytochrome oxidase, monoamine oxidase, cathepsin D, and N-acetyl-beta-glucosaminidase. Significant differences between the cell types were found for 7 of the 10 enzymes tested. The total activity of 5'-nucleotidase in cultured smooth muscle cells was 17 times that of cultured endothelial cells. Comparison of the activities in the two cell types freshly collected and in culture showed that the difference in 5'-nucleotidase in cultured cells is due principally to loss of activity from endothelial cells, suggesting that this activity is regulated differently in the two cell types. In both cell types cathepsin D activity rose during culture.
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PMID:Enzyme activities in endothelial cells and smooth muscle cells from swine aorta. 22 46

The organelle pathology of neutrophils in chronic granulocytic leukaemia (CGL) was investigated by analytical subcellular fractionation. There were minor reductions in activity of some granule enzymes with an abnormal distribution in sucrose density gradients of the specific granules. There was a marked reduction of 5'-nucleotidase activity but this is probably related to the relative reduction of the mononuclear cell contamination of the neutrophils isolated from leukaemic patients compared with controls. Another plasma membrane enzyme, NADH-nitroblue tetrazolium reductase, which has a microbicidal role, had increased activity. Neutrophils from patients with CGL had 13% the alkaline phosphatase activity of controls and were compared with neutrophils from women in the third trimester of pregnancy when the activity was increased to 8 times the control level. The latent activity, per cent inhibition by Levamisole, kinetic constants and subcellular distribution of alkaline phosphatase were similar in the three groups. It is suggested that the properties and intracellular localization of alkaline phosphatase are normal in CGL and that there is a quantitative lack of enzyme.
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PMID:Studies on the subcellular organelles of neutrophils in chronic granulocytic leukaemia with special reference to alkaline phosphatase. 28 20

3T3 and SV3T3 mouse embryo cells and a variety of other monolayer cell lines can be induced to form and shed plasma membrane vesicles by exposure to sulphydryl blocking agents including formaldehyde and N-ethyl malemide. Morphological studies show that multiple vesicles are formed and released from individual cells and that the vesicle membrane is continuous with the plasma membrane of the cell. Vesicles measure from o.1 to 15 micrometer in diameter and are free of detectable contamination with cytoplasmic membranes and organelles. Vesicles also show a 10-fold enrichment in the plasma membrane marker enzyme 5'-nucleotidase and are devoid of detectable NADH-cytochrome C reductase and succinic dehydrogenase activity which are marker enzymes for endoplasmic reticulum and mitochondria, respectively. Vesicles have a high cholesterol: phospholipid ratio and show enrichment in sphingomyelin content. They contain receptors for Con A and WGA, approximately 20 size class polypeptides and intramembranous particles. These results suggest that vesicles are derived from and have the general characteristics of plasma membranes.
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PMID:Plasma membrane vesiculation in 3T3 and SV3T3 cells. I. Morphological and biochemical characterization. 37 Jan 29

The interaction of glycoproteins of rough and smooth microsomal and Golgi membranes with Sepharose-bound lectins has been studied. One of these lectins was a crude preparation from wheat germ lipase which was found to bind primarily to N-acetyl neuraminic acid. Rough microsomes, smooth microsomes and Golgi membranes contain glycoproteins which bind to Concanavalin A (Con A specific for mannose residues) in decreasing amounts in the order indicated (rough, smooth and Golgi) and to wheat germ agglutinin (WGA, glucosamine-specific) and to the crude lipase preparation in increasing amounts in the order indicated. The small amount of binding of rough microsomes and Golgi membranes to Crotalaria (galactose-specific) increases substantially after neuraminidase treatment. Three submicrosomal particle preparations enriched either in AMPase or in NADH- or NADPH-oxidizing electron-transport enzymes contain glycoproteins which bind Con A and wheat germ agglutinin. The latter binding is sensitive to neuraminidase treatment. Two other submicrosomal particle preparations, both enriched in glucose-6-phosphatase activity, bind preferentially to WGA. This binding is, however, not sensitive to neuraminidase. Prolonged incubation with Ervilia lectin (mannose-specific) inhibits NADH-ferricyanide reductase activity, while the electron-transport chain involving cytochrome b5 is also inhibited by Crotalaria, indicating that both the flavoprotein and the cytochrome b5 are glycoproteins whose oligosaccharide chains have terminal mannose or galactose residues.
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PMID:Interaction of lectins with proteins of the endoplasmic reticulum and Golgi system of rat liver. 52 77

Homogenates of HTC cells have been fractionated by differential centrifugation (in four particulate fractions: N, M, L, P, and a supernatant S) or isopycnic banding in linear sucrose gradients. On this basis, the following subcellular organelles may be characterized: (i) Mitochondria, detected by cytochrome oxidase and succinodehydrogenase, are collected in the M and L fractions, and equilibrate, as a narrow band, at a median buoyant density of 1.18 g/cm3. (ii) Lysosomes, detected by the latent hydrolases beta-glycerophosphatase and N-acetyl-beta-glucosaminidase, are largely sedimented in the M and L fractions, and display a broad density distribution pattern with a median value of 1.17 g/cm3. This density is decreased or increased after cultivation of the cells in presence of Triton WR-1339 or Dextran 500, respectively. The behavior of cathepsin D is somewhat at variance with that of the two other hydrolases. (iii) Plasma membrane is tentatively detected by alkaline phosphodiesterase I. Largely recovered in the P fraction, this enzyme equilibrates at a median density close to that of the lysosomal hydrolases; the bulk of cholesterol and about half of the leucyl-2-naphthylamidase are closely associated with alkaline phosphodiesterase I; HTC cells do not contain typical 5'-nucleotidase. (iv) Catalase-bearing particles, of high buoyant density (1.22 g/cm3) are present, but 30-40% of the catalase is also found readily soluble. NADPH- and NADH: cytochrome c reductase, and RNA show more complex distributions. It is suggested that the former enzyme is associated with the endoplasmic reticulum; as in liver, NADH reductase activity is shared between the endoplasmic reticulum and the mitochondria; half of the RNA is associated with free ribosomes of polysomes. True glucose-6-phosphatase could not be detected.
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PMID:Analytical fractionation of cultured hepatoma cells (HTC cells). 56 43

A highly purified plasma membrane fraction was obtained from a microsomal subfraction of rat mammary gland after treatment with digitonin to increase its density. The purified membranes were enriched 70-fold overall in 5'-nucleotidase with essentially no contamination from glactosyltransferase, succinate-ING reductase, or NADPH-cytochrome c reductase. The membranes were also highly enriched in sialoglycoproteins.
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PMID:Purification of plasma membranes from rat mammary gland by a density perturbation procedure. 99

Little is known regarding the membrane properties of metastatic cells as compared to non-metastatic tumor cells. In order to remove variables such as site of growth and nutrition, C3H mice and LM fibroblasts were used as a model system to derive cell lines from local tumors and lung metastases. LM cells were injected subcutaneously into C3H mice and local skin tumors and secondary lung tumors were isolated, cultured in vitro and analyzed. The activities of lipid-sensitive membrane enzymes, membrane lipid composition, and membrane structure were correlated with metastatic ability. Plasma membranes and microsomes of the cultured metastatic cells had 3.8 +/- 0.5- and 5.4 +/- 0.6-fold elevated 5'-nucleotidase activity, respectively, as compared to plasma membranes and microsomes of cultured non-metastatic cells. The mitochondria of cultured metastatic cells had 3.5 +/- 0.5-fold decreased succinate-dependent cytochrome-c reductase activity as compared to mitochondria of the cultured non-metastatic cells. The lipids of plasma membranes from the metastatic cells had 30 +/- 2% and 46 +/- 7% lower phosphatidylinositol and sterol/phospholipid ratio, respectively, and 30 +/- 3% increased unsaturated/saturated fatty acid as compared to cultured non-metastatic cells. The lower sterol/phospholipid ratio correlated with a 30 +/- 1% lower level of cytosolic sterol carrier protein in the cultured metastatic cells as compared to cultured non-metastatic cells. Multifrequency phase and modulation fluorometry in conjunction with the fluorescence probe, 1,6-diphenyl-1,3,5-hexatriene, was used to determine the static and dynamic aspects of membrane fluidity. The plasma membranes and microsomes of cultured metastatic cells were more fluid than those of cultured non-metastatic cells as indicated by 24 +/- 3% and 7 +/- 1%, respectively, lower limiting anisotropy of 1,6-diphenyl-1,3,5-hexatriene in the membranes of the metastatic as compared to non-metastatic cells.
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PMID:Membrane properties of metastatic and non-metastatic cells cultured from C3H mice injected with LM fibroblasts. 215 60

A quantitative assay for human adrenal autoantibodies has been developed to aid in the detection and isolation of human adrenal antigens. To define the subcellular location(s) of the antigen(s) capable of binding with these antibodies, we have quantitated both antibody binding to various adrenal subcellular fractions and the adrenal autoantibody binding inhibition caused by each subcellular fraction. To further define the subcellular location of the autoantibody binding, each fraction was assayed for organelle-specific marker enzyme activities. Enzyme activities were correlated to adrenal autoantibody binding to each fraction by linear regression. Of the materials tested, both antibody binding and inhibition of binding were most highly correlated with adrenal subcellular fractions enriched with cytochrome-c reductase and 5'-nucleotidase (r = 0.98; P less than 0.05). Thus, our data support the localization of adrenal autoantigen(s) in the microsomes, plasma membrane, or both.
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PMID:Adrenal autoantibodies bind to adrenal subcellular fractions enriched in cytochrome-c reductase and 5'-nucleotidase. 229 42


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