The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform
T.d. Wilkins - One of the best experts on this subject based on the ideXlab platform.
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Purification and Characterization of Clostridium difficile Glutamate Dehydrogenase
Archives of biochemistry and biophysics, 1993Co-Authors: B.m. Anderson, C.d. Anderson, R.l. Vantassell, D.m. Lyerly, T.d. WilkinsAbstract:Recombinant Clostridium difficile glutamate dehydrogenase (L-glutamate:NAD oxidoreductase, EC 1.4.1.2) was purified 177-fold to electrophoretic homogeneity with a 62% recovery through a four-step procedure involving gel filtration and ion-exchange and dye affinity chromatography. The approximate molecular weights of the native enzyme by gel filtration and subunits by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were consistent with a hexameric structure for the purified enzyme. The enzyme-catalyzed glutamate oxidation was an NAD-dependent sequential process in which NADP could not be substituted as Coenzyme. Several dinucleotide analogs of NAD structurally altered in either the pyridine or the purine moiety were observed to function as Coenzymes when substituted for NAD. Nicotinamide mononucleotide did not serve as a Coenzyme for glutamate oxidation. Product inhibition by NADH was competitive with respect to NAD. In deadend inhibition studies, adenosine diphosphoribose was shown to be an effective Coenzyme-competitive inhibitor.
Godfried D. Vogels - One of the best experts on this subject based on the ideXlab platform.
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In vitro inhibition of cell growth of MOLT-4 malignant human T-lymphoblasts by Coenzyme F420
Biochemical Pharmacology, 1991Co-Authors: P. C. Raemakers-franken, J. G. H. Willems, Ronney A De Abreu, Chris Van Der Drift, Godfried D. VogelsAbstract:The inhibitory effect of methanogenic Coenzymes on the proliferation of MOLT-4 human malignant T-lymphoblasts was tested. Furthermore the effects of methanogenic Coenzymes on dihydrofolate reductase activity (DHFR) from chicken liver have been examined. The results showed that heat-stable extracts of the hydrogenotrophs Methanobacterium thermoautotrophicum, Methanoculleus thermophilicum and Methanogenium tationis inhibit both proliferation of human T-lymphoblasts and DHFR activity. Heat-stable extract of the methylotroph Methanosarcina barkeri showed neither inhibitory nor stimulatory effects in both test systems. The present study proves Coenzyme F420 to be the active, inhibitory component in methanogenic extracts.
Robert H. White - One of the best experts on this subject based on the ideXlab platform.
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Biosynthesis of the Methanogenic Coenzymes
Comprehensive Natural Products II, 2010Co-Authors: Laura L. Grochowski, Robert H. WhiteAbstract:Our current knowledge of the genes, enzymes, and pathways involved in the biosynthesis of the methanogenic Coenzymes methanofuran, methanopterin, Coenzyme F420, FMN, FAD, Coenzyme B, Coenzyme M, Coenzyme F430, and corrinoid factor III is updated. Proposed reaction mechanisms for several of the novel reactions involved in their biosynthesis are presented and discussed.
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Biosynthesis of the methanogenic cofactors.
Vitamins and hormones, 2001Co-Authors: Robert H. WhiteAbstract:Our current knowledge of the pathways and genes involved in the biosynthesis of the methanogenic Coenzymes methanopterin, Coenzyme B, methanofuran, Coenzyme F420, and Coenzyme M is presented. Proposed reaction mechanisms for several of the novel reactions involved in the pathways are presented.
B.m. Anderson - One of the best experts on this subject based on the ideXlab platform.
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Purification and Characterization of Clostridium difficile Glutamate Dehydrogenase
Archives of biochemistry and biophysics, 1993Co-Authors: B.m. Anderson, C.d. Anderson, R.l. Vantassell, D.m. Lyerly, T.d. WilkinsAbstract:Recombinant Clostridium difficile glutamate dehydrogenase (L-glutamate:NAD oxidoreductase, EC 1.4.1.2) was purified 177-fold to electrophoretic homogeneity with a 62% recovery through a four-step procedure involving gel filtration and ion-exchange and dye affinity chromatography. The approximate molecular weights of the native enzyme by gel filtration and subunits by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were consistent with a hexameric structure for the purified enzyme. The enzyme-catalyzed glutamate oxidation was an NAD-dependent sequential process in which NADP could not be substituted as Coenzyme. Several dinucleotide analogs of NAD structurally altered in either the pyridine or the purine moiety were observed to function as Coenzymes when substituted for NAD. Nicotinamide mononucleotide did not serve as a Coenzyme for glutamate oxidation. Product inhibition by NADH was competitive with respect to NAD. In deadend inhibition studies, adenosine diphosphoribose was shown to be an effective Coenzyme-competitive inhibitor.
Pier Giorgio Righetti - One of the best experts on this subject based on the ideXlab platform.
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Capillary electrophoresis of nicotinamide—adenine dinucleotide and nicotinamide—adenine dinucleotide phosphate derivatives in coated tubular columns
Journal of Chromatography A, 1994Co-Authors: Marina Nesi, Marcella Chiari, Giacomo Carrea, Gianluca Ottolina, Pier Giorgio RighettiAbstract:Abstract HPCE was shown to be an effective and convenient method for the determination of nicotinamide—adenine dinucleotide (oxidized, NAD + ; reduced, NADH), nicotinamide—adenine dinucleotide phosphate (oxidized, NADP; reduced, NADPH) and their synthetic derivatives. The Coenzymes were easily separated among themselves and from their degradation products, which are inhibitors of dehydrogenases, in 15 min in a coated capillary. Several Coenzyme derivatives such as N 6 -(2-aminoethyl)-NAD(P) + and N(1)-(2-aminoethyl)-NAD(P) + were separated by zone electrophoresis in uncoated or coated capillaries using 50 m M 3-(N-morpholino)propanesulphonic acid (pH 7.0) or Tris—HCl (pH 8.0) as buffer systems. Capillary zone electrophoresis and micellar electrokinetic capillary chromatography can also be used to monitor continuously Coenzyme chemical modifications.