Thermodynamic control of electron flux through mitochondrial cytochrome bc1 complex
- 15 January 1985
- journal article
- research article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 225 (2) , 399-405
- https://doi.org/10.1042/bj2250399
Abstract
The redox states of exogenously added ubiquinone-2 and cytochrome c, and the protonmotive force (delta p) of rat liver mitochondria were measured as the respiration rate was titrated with the uncoupler carbonyl cyanide p-trifluoromethoxyphenyl-hydrazone. The force ratio delta Eh/delta p across the bc1 complex was close to 1:1 in State 4, indicating an H+/e- stoichiometry of 1:1 for the cytochrome bc1 complex, excluding protons moved by pool ubiquinone. Assuming a constant stoichiometry the rate of electron transport increased linearly with the disequilibrium (delta Eh - delta p) across the complex.This publication has 18 references indexed in Scilit:
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