Galkin 2006 Biochim Biophys Acta
|Galkin A, Dröse S, Brandt U (2006) The proton pumping stoichiometry of purified mitochondrial Complex I reconstituted into proteoliposomes. Biochim Biophys Acta 1757:1575-81.|
Abstract: NADH:ubiquinone oxidoreductase (Complex I) is the largest and most complicated enzyme of aerobic electron transfer. The mechanism how it uses redox energy to pump protons across the bioenergetic membrane is still not understood. Here we determined the pumping stoichiometry of mitochondrial Complex I from the strictly aerobic yeast Yarrowia lipolytica. With intact mitochondria, the measured value of the 3.8 H+/2 ē indicated that four protons are pumped per NADH oxidized. For purified Complex I reconstituted into proteoliposomes we measured a very similar pumping stoichiometry of 3.6 H+/2 ē. This is the first demonstration that the proton pump of Complex I stayed fully functional after purification of the enzyme.
• Keywords: Complex I, NADH:ubiquinone oxidoreductase, Proton pump, Energy transduction, Mitochondria, Proteoliposome, Yarrowia lipolytica
Labels: MiParea: Respiration
Preparation: Isolated mitochondria Enzyme: Complex I
Coupling state: OXPHOS