H+/e- stoichiometry of mitochondrial cytochrome complexes reconstituted in liposomes. Rate-dependent changes of the stoichiometry in the cytochrome c oxidase vesicles.
The H+/e- stoichiometry of protonmotive cytochrome c oxidase, isolated from bovine heart mitochondria and reconstituted in liposomes, has been determined by making use of direct spectrophotometric measurements of the initial rates of e- flow and H+ translocation. It is shown that the ----H+/e- ratio for redox-linked proton ejection by the oxidase varies from around 0 to a maximum of 1 as a function of the rate of overall electron flow in the complex.
Capitanio
N
N
Institute of Medical Biochemistry and Chemistry, Faculty of Medicine, University of Bari, Italy.
Capitanio
G
G
De Nitto
E
E
Villani
G
G
Papa
S
S
D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism; D002417:Cattle; D004579:Electron Transport / Q000502:physiology*; D003576:Electron Transport Complex IV / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008081:Liposomes / Q000378:metabolism; D008929:Mitochondria, Heart / Q000378:metabolism*; D009245:NADH Dehydrogenase / Q000378:metabolism; D013053:Spectrophotometry
D008081:Liposomes; D006859:Hydrogen; D009245:NADH Dehydrogenase; D003576:Electron Transport Complex IV; D001205:Ascorbic Acid