title: Mitochondrial hydrogen peroxide production as determined by the pyridine nucleotide pool and its redox state.
abstract: The rates of NADH-supported superoxide/hydrogen peroxide production by membrane-bound bovine heart respiratory complex I, soluble pig heart dihydrolipoamide dehydrogenase (DLDH), and by accompanying operation of these enzymes in rat heart mitochondrial matrix were measured as a function of the pool of pyridine nucleotides and its redox state. Each of the activities showed nontrivial dependence on nucleotide pool concentration. The NAD(+)/NADH ratios required for their half maximal capacities were determined. About half of the total NADH-supported H(2)O(2) production by permeabilized mitochondria in the absence of stimulating ammonium could be accounted for by DLDH activity. The significance of the mitochondrial NADH-dependent hydrogen peroxide production under physiologically relevant conditions is discussed. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).
authors.affiliation: Department of Biochemistry, Moscow State University, Moscow, Russian Federation.
authors.forename: Alexandra V
authors.initials: AV
authors.lastname: Kareyeva
authors.forename: Vera G
authors.initials: VG
authors.lastname: Grivennikova
authors.forename: Andrei D
authors.initials: AD
authors.lastname: Vinogradov
mesh_terms: D000818:Animals; D002417:Cattle; D008058:Dihydrolipoamide Dehydrogenase / Q000378:metabolism*; D042967:Electron Transport Complex I / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008929:Mitochondria, Heart / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism*; D009243:NAD / Q000378:metabolism*; D009249:NADP / Q000378:metabolism*; D051381:Rats; D013552:Swine
chemical_list: D024101:Mitochondrial Proteins; D009124:Muscle Proteins; D009243:NAD; D009249:NADP; D006861:Hydrogen Peroxide; D008058:Dihydrolipoamide Dehydrogenase; D042967:Electron Transport Complex I