Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

NADP-dependent glutamate dehydrogenase (NADP-GDH) was purified to homogeneity from Pseudomonas aeruginosa strain 8602 (PAC 1). The Mr determined by Sephadex gel filtration was 280,000; the subunit Mr determined by SDS-PAGE was 45,000. Mutant strains lacking NADP-GDH and glutamate synthase (Gdh-Glt-) required glutamate for growth. Transductants that lacked only NADP-GDH were indistinguishable from the wild-type strain in growth properties. It was concluded that NADP-GDH is not essential for growth of the wild-type organism and that glutamate formation via NAD-dependent glutamate dehydrogenase does not occur to a significant extent. A mutant strain, 39, producing high NADP-GDH activity, synthesized normal NADP-GDH and had the same intracellular glutamate concentrations as its parent. The mutation responsible for the synthesis of high levels of NADP-GDH was shown, by transduction, to be closely linked to the NADP-GDH structural gene (gdhA).
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PMID:Mutations affecting the synthesis of NADP-dependent glutamate dehydrogenase in Pseudomonas aeruginosa. 284 62

NAD glycohydrolase (NADase) (E.C. 3.2.2.5) from five-pace snake (Agkistrodon acutus) venom was purified to electrophoretic homogeneity through a 4-step isolation procedure, including column chromatography using DEAE-Sephadex A-50, Sephadex G-75, CM Sephadex C-50 and Sephadex G-100. The final product was 11.8-fold purified with a 3.9% yield. The pure enzyme showed maximal activity at about 40 degrees C with optimal pH at 7.5. It was a glycoprotein with a pI of 7.6. Its mol. wt was respectively 98,000 as measured by gel filtration and 50,000, by SDS-PAGE. There was only one N-terminal residue, proline. NADase is thus composed of two identical subunits in each molecule. The enzyme contained copper ions. NADase activity was lost when the copper enzyme complex was treated with EDTA. The Km of the enzyme for beta-NAD, NADP and beta-NGP were 0.50 mM, 0.13 mM and 0.16 mM respectively.
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PMID:Properties of NAD glycohydrolase purified from five-pace snake (Agkistrodon acutus) venom. 284 6

NADPH-cytochrome P-450 reductase in rat testicular microsomal fraction was solubilized by trypsin, and purified to apparent homogeneity in polyacrylamide gel electrophoresis. Molecular weight of the enzyme was estimated to be about 70,000 by SDS-polyacrylamide gel electrophoresis. Km values were estimated as 18 microM for cytochrome c, 17 microM for dichlorophenol indophenol (DCPIP), 50 microM for K3Fe (CN)6 and 1.7 microM for NADPH. The cytochrome c reducing activity of the purified preparation was decreased by tetranitromethane (TNM), a reagent for nitration of tyrosine residues in a protein. The inactivation exhibited pseudo-first-order kinetics. A plot of log kapp vs log [TNM] gave a straight line with slope = 1.05, indicating the reaction of one modifier molecule in the inactivation process. The decrease of the reducing activities for DCPIP and K3Fe(CN)6 by TNM progressed more slowly than that for cytochrome c. The inactivation of cytochrome c reduction was protected completely by 0.1 mM NADP(H) and partially by 0.1 mM DCPIP and cytochrome c. No preventive change of the inactivation by TNM was observed by addition of NAD+ or testosterone. On the other hand, the differential modification by DTNB, TNM and DTT indicated that there were amino acid residues modified by TNM, such as tyrosine residues, at or near the active-site of the NADPH-cytochrome P-450 reductase.
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PMID:Purification of NADPH-cytochrome P-450 reductase from microsomal fraction of rat testes, and its chemical modification by tetranitromethane. 309 39

Reaction of deoxy-Hb with the periodate-oxidized derivatives of nicotinamide adenine dinucleotide (o-NAD), phosphoribosyl pyrophosphate (o-PRPP), adenosine triphosphate (o-ATP), glucose-1-phosphate (o-glc-1-P) and nicotinamide adenine dinucleotide phosphate (o-NADP) led to formation of cross-link adducts in varying yields as determined by SDS-polyacrylamide gel electrophoresis. Oxygen equilibrium studies were performed on Hb's cross-linked with o-NAD, o-PRPP and o-ATP. These derivatives were found to have increased oxygen affinity and were cross-linked between the beta chains. Inositol hexaphosphate (IHP) blocked modification by these reagents, suggesting that modification was occurring in the organic phosphate binding site. In addition, it was found that the bifunctional reagent 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS) also led to formation of Hb cross-linked between the beta chains, but resulted in a derivative with a dramatically decreased oxygen affinity, properties making it a potential candidate as an Hb-based cell-free blood substitute.
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PMID:Modification of hemoglobin with site-directed bifunctional reagents. 312 Apr 83

3 alpha-Hydroxyglycyrrhetinate dehydrogenase of Clostridium innocuum, isolated from human intestinal bacteria, was capable of converting 3-ketoglycyrrhetic acid to 3 alpha-hydroxyglycyrrhetic acid. The enzyme was purified to homogeneity by means of butyl-Toyopearl 650M, Sephadex G-150, Matrex Red A, Toyopearl HW-55S, and isoelectric focusing column chromatographies. The purified enzyme showed a specific activity of 156 mumol/min.mg toward 3 alpha-hydroxyglycyrrhetic acid, and showed a single band on SDS-polyacrylamide gel electrophoresis. The apparent molecular weight was 53,000, as estimated by gel filtration, and 30,000, as judged by SDS-polyacrylamide gel electrophoresis. Its isoelectric point was 5.2. The enzyme showed absolute specificity for the 3 alpha-hydroxyl and 3-ketonic groups of 18 alpha- or 18 beta-glycyrrhetic acid and required NADP+ and NADPH as cosubstrates. The enzyme did not act on any 3 alpha-hydroxyl or 3-ketonic group of steroids or bile acids. The enzyme is a novel type of enzyme, defined as 3 alpha-hydroxy-glycyrrhetinate dehydrogenase, being quite different from 3 alpha-hydroxysteroid dehydrogenase [EC 1.1.1.50].
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PMID:Purification and properties of 3 alpha-hydroxyglycyrrhetinate dehydrogenase of Clostridium innocuum from human intestine. 316 18

NADP-hydrazidoadipoyl oxypropyl sepharose was synthesized from epoxyactivated sepharose through a hydrazid derivative and used for isolation of NADP(H)-dependent enzymes such as glutathione reductase, isocitrate dehydrogenase and malate dehydrogenase. The isolation technique involves fractionation with ammonium sulphate, affinity chromatography on NADP-hydrazidoadipoyl oxypropyl sepharose and chromatography on hydroxylapatite. The proposed technique enabled the authors to obtain malate dehydrogenase isocitrate dehydrogenase and glutathione reductase preparations homogeneous according to SDS-electrophoresis in polyacrylamide gel.
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PMID:[Isolation of highly-purified NADP(H)-dependent enzymes from the rat liver using NADP-hydrazidoadipoyl oxypropyl sepharose]. 317 4

5-Ketofructose reductase [D(-)fructose:(NADP+) 5-oxidoreductase] was purified to homogeneity from Erwinia citreus and demonstrated to catalyse the reversible NADPH-dependent reduction of 5-ketofructose (D-threo-2,5-hexodiulose) to D-fructose. The enzyme appeared as a single species upon analyses by SDS/polyacrylamide-gel electrophoresis and isoelectric focusing with an apparent relative molecular mass of 40,000 and an isoelectric point of 4.4. The amino acid composition of the enzyme and the N-terminal sequence of the first 39 residues are described. The steady-state kinetic mechanism was an ordered one with NADPH binding first to the enzyme and then to 5-ketofructose, and the order of product release was D-fructose followed by NADP+. The reversible nature of the reaction offers the possibility of using this enzyme for the determination of D-fructose.
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PMID:Purification and characterization of 5-ketofructose reductase from Erwinia citreus. 317 25

An electrophoretically homogeneous preparation of mitochondrial NADP-dependent malate dehydrogenase with a specific activity of 155 u./mg and a 67% yield has been obtained, using ammonium sulfate fractionation, gel filtration through Toyopearl HW-55 F, ion-exchange chromatography on DEAE-Toyopearl 650 M and affinity chromatography on 2',5'-ADP-Sepharose 4B. The molecular mass of native malate dehydrogenase is 260 kD; Mr of the SDS-treated enzyme is 61 kD, which is suggestive of a tetrameric structure of the protein. Malate dehydrogenase is active only in the presence of Mg2+ or Mn2+, but not Ca2+ or Ba2+. The Km' values for Mn2+ and Mg2+ are 50 and 66 microM, respectively. At low malate concentrations and NADP saturation, the enzyme is characterized by a sigmoidal kinetics which changes to hyperbolic at low concentrations of NADP. The Lineweaver--Burk plots for the dependence of the initial reaction rate on the concentration of one substrate at several fixed concentrations of the other substrate intersect to the left of the B-axis. NADPH competes with NADP:pyruvate inhibits malate dehydrogenase ++noncompetitively with respect to the coenzyme. NADPH and pyruvate inhibit the malate dehydrogenase-catalyzed reaction via a mixed type mechanism with respect to malate. The data obtained are consistent with a consecutive mechanism of reaction, whose first substrate is NADP and the last product is NADPH.
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PMID:[Purification and properties of NADP-specific malate dehydrogenase from bovine adrenal cortex mitochondria]. 325 46

We have succeeded in purifying to homogeneity a very labile NADP+-linked isocitrate dehydrogenase (isocitrate: NADP+ oxidoreductase (decarboxylating), EC 1.1.1.42) from a strain of alkalophilic Bacillus, by a simple method, with an overall yield over 76% of the original activity. The molecular weight on Sephadex G-200 was around 90,000; and that by electrophoresis on SDS-polyacrylamide gels was about 44,000. The sedimentation coefficient (s020,w) and isoelectric point of the enzyme were determined to be 3.22 S and pH 4.7, respectively. The enzyme required Mn2+ for the reaction and for stability. The optimum pH for the reaction was in the range 7.8-8.4 at 30 degrees C; the optimum temperature at pH 8.0 was 75 degrees C; the activation energy of the reaction was 6.2 kcal/mol. The Km values for threo-Ds-isocitrate, DL-isocitrate, and NADP+ were 5.4 microM, 9.9 microM, and 7.3 microM, respectively. This enzyme was inhibited by NADPH, glyceraldehyde 3-phosphate, 3-phosphoglycerate, phosphoenol pyruvate, cis-aconitate, alpha-ketoglutarate, and oxaloacetate. In addition, it was subject to a concerted inhibition by a combination of glyoxylate and oxaloacetate, and also to a cumulative inhibition by nucleoside triphosphates.
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PMID:Purification and characterization of NADP+-linked isocitrate dehydrogenase from an alkalophilic Bacillus. 333 29

7 beta-Hydroxysteroid dehydrogenase (7 beta-HSD) was produced by Ruminococcus sp. PO1-3 obtained from among human intestinal bacteria. The enzyme was purified from a crude extract by ammonium sulfate fractionation, and Butyl-Toyopearl 650M, Sephadex G-150, Matrex Red A and Octyl-Sepharose chromatographies. The purified enzyme was obtained as a single band on polyacrylamide gel electrophoresis with enzyme activity staining and as one band corresponding to a molecular weight of 30,000 on SDS-polyacrylamide gel electrophoresis. On gel filtration, its apparent molecular weight was estimated to be 60,000. The enzyme had a sulfhydryl group(s) in its active site. Substrate specificity studies revealed that the enzyme showed absolute specificity for the beta-configuration of a hydroxyl group at the 7 position of bile acids, and required NADP+ and NADPH as cosubstrates. The Km values for ursodeoxycholic acid, 7-k etolithocholic acid, NADP+, and NADPH were 5.0, 8.5, 7.7, and 24 microM, respectively.
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PMID:Purification and characterization of 7 beta-hydroxysteroid dehydrogenase from Ruminococcus sp. of human intestine. 348 Aug 90


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