Evidence for a role of a vicinal dithiol in catalysis and proton pumping in mitochondrial nicotinamide nucleotide transhydrogenase
The effect of glutathione, glutathione disulfide and the dithiol reagent phenylarsine oxide on purified soluble as well as reconstituted mitochondrial nicotinamide nucleotide transhydrogenase from beef heart was investigated. Glutathione disulfide and phenylarsine oxide caused an inhibition of transhydrogenase, the extent of which was dependent on the presence of either of the transhydrogenase substrates. In the absence of NADPH glutathione protected partially against inactivation by glutathione disulfide and phenylarsine oxide. In the presence of NADPH glutathione also inhibited transhydrogenase. Reconstituted transhydrogenase vesicles behaved differently as compared to the soluble transhydrogenase and was partially uncoupled by GSSG. It is concluded that transhydrogenase contains a dithiol that is essential for catalysis as well as for proton translocation.
- Research Organization:
- Univ. of Stockholm, Sweden
- OSTI ID:
- 6934853
- Journal Information:
- Biochem. Biophys. Res. Commun.; (United States), Journal Name: Biochem. Biophys. Res. Commun.; (United States) Vol. 2; ISSN BBRCA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biosynthesis of transhydrogenase in vitro and in vivo
Ca/sup 2 +/ transport against its electrochemical gradient in cytochrome oxidase vesicles reconstituted with mitochondrial hydrophobic proteins
Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ARSENIC COMPOUNDS
BARYONS
BIOLOGICAL EFFECTS
CELL CONSTITUENTS
COENZYMES
DISULFIDES
DRUGS
ELEMENTARY PARTICLES
ENZYME ACTIVITY
ENZYMES
FERMIONS
GLUTATHIONE
HADRONS
HYDROGENASES
MITOCHONDRIA
NAD
NADP
NUCLEONS
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANOIDS
OXIDOREDUCTASES
PEPTIDES
POLYPEPTIDES
PROTEINS
PROTONS
RADIOPROTECTIVE SUBSTANCES