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V W Rodwell

Publications and source records attributed to V W Rodwell.

86 records · Page 5Linked to original sources

Alpha-hydroxyglutarate oxidoreductase of Pseudomonas putida.

Oxidation of d-alpha-hydroxyglutarate to alpha-ketoglutarate is catalyzed by d-alpha-hydroxyglutarate oxidoreductase, an inducible membrane-bound enzyme of the electron transport particle [ETP; a comminuted cytoplasmic membrane preparation with enzymic properties and chemical composition resembling beef heart mitochondrial ETP (1)] of Pseudomonas putida P2 (P2-ETP). Treatment of P2-ETP with a nonionic detergent yields a preparation with the sedimentation characteristics of a soluble enzyme, but which retains an intact electron transport chain. Oxygen acts solely as a terminal electron acceptor and may be replaced by ferricyanide, 2,6-dichlorophenol indophenol, or mammalian cytochrome c. The oxidoreductase is specific for the d-isomer (K(m) = 4.0 x 10(-4)m for dl-alpha-hydroxyglutarate) and is distinct both from l- and d-malate dehydrogenases. Spectral studies suggest that the carrier sequence is substrate --> flavine or nonheme iron --> cyt b --> [cyt c] --> oxygen.

Alcohol Oxidoreductases↗

Bacterial metabolism of mevalonic acid.

Soluble cell-free extracts of actinomycete S4 grown on media containing mevalonate catalyze acetoacetate formation from mevalonate, mevaldate, and beta-hydroxy-beta-methylglutaryl-coenzyme A (CoA). Conversion of mevalonate to acetoacetate involves formation of free beta-hydroxy-beta-methylglutaryl-CoA, but not free mevaldate. The reaction favors mevalonate oxidation, and nicotinamide adenine dinucleotide, rather than nicotinamide adenine dinucleotide phosphate, acts as oxidant.

Acetoacetates↗

Metabolism of pipecolic acid in a Pseudomonas species. V. Pipecolate oxidase and dehydrogenase.

Oxidation of pipecolate to Delta(1)-piperideine-6-carboxylate is catalyzed by pipecolate oxidase, an inducible, membrane-bound dehydrogenase associated with the electron transport components of Pseudomonas putida P2. From the oxidase, we obtained a smaller particle containing flavine adenine dinucleotide (FAD) and cytochrome b, but no longer able to catalyze electron transfer to oxygen or to cytochrome c. Certain properties of this l-pipecolate dehydrogenase, an FAD-flavoprotein, are reported.

Cytochromes↗

Metabolism of Pipecolic Acid in a Pseudomonas Species IV. Electron Transport Particle of Pseudomonas putida.

Baginsky, Marietta L. (University of California, San Francisco Medical Center, San Francisco), and Victor W. Rodwell. Metabolism of pipecolic acid in a Pseudomonas species. IV. Electron transport particle of Pseudomonas putida. J. Bacteriol. 92:424-432. 1966.-Enzymes of Pseudomonas putida P2 catalyzing oxidation of pipecolate to Delta(1)-piperideine-6-carboxylate are located in a subcellular fraction sedimenting at 105,000 x g. Since this fraction resembles the mammalian electron transport particle in both chemical composition and enzymatic activities, it was termed Pseudomonas P2 electron transport particle (P2-ETP). P2-ETP contains flavin adenine dinucleotide, flavin mononucleotide, iron, copper, and both b- and c-type cytochromes. The reduced type b cytochrome has absorption maxima at 558 to 559, 530, and 427 mmu. Its oxidized pyridine hemochromogen has an absorption maximum at 406 mmu, with a shoulder at 564 mmu. On dithionite reduction, absorption bands with maxima at 556, 522, and 418 mmu are obtained. The reduced type c cytochrome has absorption maxima at 552, 520, and 422 mmu; its reduced pyridine hemochromogen has maxima at 551, 516 to 519, and 418 mmu. No type a cytochrome was detected. P2-ETP catalyzes oxidation of pipecolate and of reduced nicotinamide adenine dinucleotide (NADH(2)) by oxygen. It can also oxidize these compounds, as well as succinate and reduced nicotinamide adenine dinucleotide phosphate, with 2,6-dichlorophenol-indophenol as electron acceptor. Mammalian cytochrome c can be used as an alternate artificial electron acceptor for the oxidation of pipecolate and succinate, but not for oxidation of NADH(2).

Journal Article↗