Respiratory complex I: structure, redox components, and possible mechanisms of energy transduction.
Structural arrangements and properties of redox components of the mitochondrial and bacterial proton-translocating NADH:quinone oxidoreductases are briefly described. A model for the mechanism of proton translocation at first coupling site, which emphasizes participation of specifically Complex I-associated ubisemiquinones, is discussed. An alternative mechanism is proposed where all redox reactions take place in a hydrophilic part of the enzyme and the free energy accumulated as conformational constraint drives the proton pump associated with the hydrophobic polypeptides.
Vinogradov
A D
AD
Department of Biochemistry, School of Biology, Lomonosov Moscow State University, Moscow, 119899, Russia. adv@biochem.bio.msu.su
D000818:Animals; D004563:Electrochemistry; D042967:Electron Transport Complex I; D004735:Energy Transfer; D005415:Flavins / Q000378:metabolism; D007501:Iron / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry* / Q000378:metabolism*; D010084:Oxidation-Reduction; D011485:Protein Binding; D011487:Protein Conformation; D017494:Proton Pumps / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism; D014451:Ubiquinone / Q000378:metabolism
D005415:Flavins; D017494:Proton Pumps; D014451:Ubiquinone; D013455:Sulfur; D007501:Iron; D009247:NADH, NADPH Oxidoreductases; D042967:Electron Transport Complex I