Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q8NEX9 (reductase)
 26,410 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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 leukocytes of exudate from diabetic rabbits, the activities of hexokinase, phosphoglucomutase and glucose-6-phosphate dehydrogenase are increased, and a tendency of adenylate kinase activity to decline is observable. The activities of UDP-pyrophosphatase, UDP-glycogentransferase, 6-phosphogluconate dehydrogenase and glutahione reductase in the exudate erythrocytes in diabetes are not essentially altered. The decrease of the key enzymes of glycolysis and pentose phosphate cycle, providing the leukocytes with energy and metabolites, reduces the functional activity of leukocytes from exudate in diabetes.
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PMID:[Enzyme profile of exudate leukocytes from diabetic rabbits]. 51 96

During the rat weaning period (about day 19 after birth) the intestinal maturation is accompanied by a drastic increase in the fucose content of mucosal glycoconjugates, concomitant with an increase in fucosyltransferase activities. The regulation of this fucosylation process appears to be a rather complex phenomenon, which involves several systems controlling fucosyltransferase activity or substrate availability. An endogenous protein inhibitor of the fucosyltransferase activities displays an opposite developmental pattern to that of fucosyltransferase activities, since its activity is high before weaning and is decreased 5-fold after weaning. Similarly, the GDP-fucose pyrophosphatase activity markedly decreases at weaning. The transformation of GDP-mannose into GDP-fucose increases early, at day 18, preceding the increase in fucosyltransferase activities. Before weaning, and especially at days 14 and 18, high levels of GDP-4-dehydro-6-deoxymannose, the product of the GDP-mannose 4,6-dehydratase activity, are produced during the transformation of GDP-mannose into GDP-fucose, even in excess of reduced coenzyme. This fact indicates that the second step of the transformation (epimerase-reductase reaction) could be a limiting factor for GDP-fucose availability before weaning, but not after weaning. The inverse relationship between the mucosal fucose content (or the fucosyltransferase activity) and the endogenous protein inhibitor during normal postnatal development supports the hypothesis of a physiological role for this inhibitor.
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PMID:Participation of an endogenous inhibitor of fucosyltransferase activities in the developmental regulation of intestinal fucosylation processes. 195 74

Effects of dibutyryl cyclic AMP on enzymatic reaction for the thiamine pyrophosphatase, NADPH-tetrazolum, reductase, adenosine--triphosphatas -Ca-formol and acid phosphatase were investigated in the intestinal epithelium of the salivectomised mice. After intraperitoneal injections of dibutyryl cyclic AMP a marked increase of enzymatic reaction for thiamine pyrophosphatase (a marker of the Golgi complex) was noted, especially after 4 injections of dibutyryl cyclic AMP (twenty four hours after first injection). At the same time the intensities of reaction for the NADPH-r.t., ATP-ase-Ca-Formol and AcP did not undergo any changes in epithelial cells of intestinal villi after salivectomy and after dibutyrylo cyclic AMP administration. The obtained results suggest that dibutyrylo cyclic AMP probably regulates the Golgi complex activity.
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PMID:Effect of dibutyrylo cyclic AMP on Golgi complex activity in the intestinal epithelial cells of salivectomised mice. 196 7

The effects of submaxillary gland factor on the thiamine pyrophosphatase, 5-nucleotidase (the markers of Golgi complex), adenosine-triphosphatase, NADPH-tetrazolum reductase and acid phosphatase were studied in the intestinal epithelium of mice. A decreased intensity of histochemical reactions for the markers of Golgi's complex after salivectomy and an increased activity after homogenate injection were confirmed. The reaction intensity to NADPH-tetrazolium reductase, adenosine-triphosphatase and acid phosphatase after salivectomy and after homogenate injection were similar to those of the control mice with sham operations. On the basis of investigations performed, this provides support, that submaxillary glands produce a factor which controls Golgi complex activity and may influence on glycocalyx synthesis.
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PMID:The influence of submaxillary gland factor upon Golgi complex activity in jejunum epithelial cell of mice. 214 22

A continuous fluorometric assay for enzyme activities which remove ADP-ribose linked to proteins at arginine was developed. The substrate analog, N alpha-dansyl-N omega-(1,N6-etheno-ADP-ribosyl)arginine methyl ester, was used to assay the catalytic activities of dinitrogenase reductase activating glycohydrolase from Rhodospirillum rubrum and nucleotide pyrophosphatase from Crotalus adamanteus. The assay is based on the increase in fluorescent emission by ethenoadenine accompanying the enzyme-catalyzed hydrolysis of the substrate. The assay has been used to detect activities of 10 fmol substrate cleaved per minute. The substrate anomerizes to give a 40:60 equilibrium of alpha:beta ribosylguanidinium anomers, allowing the determination of enzyme stereospecificity. The substrate was used to determine the kinetic parameters and products of the N-glycohydrolase and the pyrophosphatase.
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PMID:Fluorometric assay for ADP-ribosylarginine cleavage enzymes. 303 20

More than twenty different enzyme activities of fractions containing dictyosome-like structures (DLS) as a dominant cell component were monitored. Plasma membrane vesicles were a major contaminant of the DLS fractions, which, presumably as a consequence, were enriched somewhat in plasma membrane markers. The lysosomal enzymes arylsulfatase and latent acid phosphatase were present in the DLS fractions as were the Golgi apparatus activities thiamine pyrophosphatase and nucleoside diphosphatase. The presence of the latter two enzymes in DLS, plus NADH-ferricyanide reductase, has been verified from cytochemistry. On the other hand, the Golgi apparatus marker, galactosyltransferase, was not enriched in DLS fractions and appeared to be absent. This latter finding, verified from cytochemistry with isolated DLS fractions and, in situ, from [3H]galactose incorporation by testis tubules with analysis by autoradiography, provides the first clear biochemical characteristic that serves unequivocally to distinguish DLS from conventional Golgi apparatus.
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PMID:Dictyosome-like structures from guinea-pig testes lack galactosyltransferase, a Golgi apparatus marker. 392 20

The rat ganglion nodosum was used to study chromatolysis following axon section. After fixation by aldehyde perfusion, frozen sections were incubated for enzyme activities used as markers for cytoplasmic organelles as follows: acid phosphatase for lysosomes and GERL (a Golgi-related region of smooth endoplasmic reticulum from which lysosomes appear to develop) (31-33); inosine diphosphatase for endoplasmic reticulum and Golgi apparatus; thiamine pyrophosphatase for Golgi apparatus; acetycholinesterase for Nissl substance (endoplasmic reticulum); NADH-tetra-Nitro BT reductase for mitochondria. All but the mitochondrial enzyme were studied by electron microscopy as well as light microscopy. In chromatolytic perikarya there occur disruption of the rough endoplasmic reticulum in the center of the cell and segregation of the remainder to the cell periphery. Golgi apparatus, GERL, mitochondria and lysosomes accumulate in the central region of the cell. GERL is prominent in both normal and operated perikarya. Electron microscopic images suggest that its smooth endoplasmic reticulum produces a variety of lysosomes in several ways: (a) coated vesicles that separate from the reticulum; (b) dense bodies that arise from focal areas dilated with granular or membranous material; (c) "multivesicular bodies" in which vesicles and other material are sequestered; (d) autophagic vacuoles containing endoplasmic reticulum and ribosomes, presumably derived from the Nissl material, and mitochondria. The number of autophagic vacuoles increases following operation.
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PMID:Lysosomes and GERL in normal and chromatolytic neurons of the rat ganglion nodosum. 429 14

Structures superficially resembling dictyosomes of Golgi apparatus are present in guinea pig spermatocytes and in spermatids in late stages of development. They coexist with Golgi apparatus. In this report, we demonstrate that the dictyosome-like structures (DLS) and Golgi apparatus share cytochemical "markers", inosine diphosphatase and thiamine pyrophosphatase. Additionally, the cytochemical marker for the mature face of conventional Golgi apparatus as well as most plasma membranes, a glutaraldehyde-resistant NADH-ferricyanide reductase, is present in DLS. The latter reaction is also given by the membranes of the acrosome and that portion of the conventional Golgi apparatus (i.e., the thick cisternae) presumed to be responsible for acrosome formation. A distinguishing feature between DLS and Golgi apparatus is in the distribution of reaction product. Golgi apparatus reaction product is concentrated toward one face of each dictyosome while DLS reaction product is usually randomly distributed across the stacks.
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PMID:Cytochemical demonstration of NADH-ferricyanide reductase and nucleoside diphosphatase activities in dictyosome-like structures of guinea pig spermatocytes. 610 24

This study confirms that zinc is able to inhibit hepatic microsomal drug metabolism and the related oxidation of NADPH. Zinc activates microsomal pyrophosphatase, a zinc-containing enzyme capable of metabolizing both NADPH and NADH. Although this reaction produces a potent inhibitor of drug metabolism, 2',5'-ADP', the activation of pyrophosphatase by zinc was found not to be solely responsible for the zinc-dependent inhibition of drug metabolism. Zinc was seen to inhibit drug metabolism in the presence of 5'-AMP, which inhibits pyrophosphatase. Incubation of zinc with microsomes prior to the addition of NADPH caused an interaction between zinc and the microsomal enzymes that was not reversed by NADPH. Zinc was found to exhibit noncompetitive inhibition of cytochrome c reduction and mixed inhibition of drug metabolism, with respect to NADPH. Zinc inhibition of drug metabolism was noncompetitive with drug substrate. Zinc was found to interact with cytochrome P-450, decreasing its ability to bind to both drugs and carbon monoxide. Zinc had a far greater effect on the reduction of cytochrome P-450 (90% inhibited) than on the reduction of exogenous cytochrome c (20% inhibited), although the same reductase is responsible for both reactions. It is concluded that zinc inhibits drug metabolism either by alteration of the oxidation-reduction potential of the flavoprotein or by interacting with a flavoprotein/cytochrome P-450 complex.
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PMID:The effect of zinc on NADPH oxidation and monooxygenase activity in rat hepatic microsomes. 613 32


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