Skip to Main content Skip to Navigation
Journal articles

A common coupling mechanism for A-type heme-copper oxidases from bacteria to mitochondria

Abstract : Mitochondria metabolize almost all the oxygen that we consume, reducing it to water by cytochrome c oxidase (CcO). CcO maximizes energy capture into the protonmotive force by pumping protons across the mitochondrial inner membrane. Forty years after the H+/e- stoichiometry was established, a consensus has yet to be reached on the route taken by pumped protons to traverse CcO's hydrophobic core and on whether bacterial and mitochondrial CcOs operate via the same coupling mechanism. To resolve this, we exploited the unique amenability to mitochondrial DNA mutagenesis of the yeast Saccharomyces cerevisiae to introduce single point mutations in the hydrophilic pathways of CcO to test function. From adenosine diphosphate to oxygen ratio measurements on preparations of intact mitochondria, we definitely established that the D-channel, and not the H-channel, is the proton pump of the yeast mitochondrial enzyme, supporting an identical coupling mechanism in all forms of the enzyme.
Document type :
Journal articles
Complete list of metadatas

Cited literature [73 references]  Display  Hide  Download
Contributor : Marie-Claude Serre <>
Submitted on : Friday, November 20, 2020 - 10:24:48 AM
Last modification on : Tuesday, December 1, 2020 - 2:20:04 PM


Marechal et al 2020.pdf
Publication funded by an institution




Amandine Maréchal, Jing-Yang Xu, Naho Genko, Andrew M. Hartley, Francis Haraux, et al.. A common coupling mechanism for A-type heme-copper oxidases from bacteria to mitochondria. Proceedings of the National Academy of Sciences of the United States of America , National Academy of Sciences, 2020, ⟨10.1073/pnas.2001572117⟩. ⟨hal-02547877⟩



Record views


Files downloads