REVIEW: Generation of Membrane Potential by Cytochrome bd

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Vitaliy B. Borisov^a

Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia

Received June 10, 2023; Revised July 8, 2023; Accepted July 11, 2023

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An overview of current notions on the mechanism of generation of a transmembrane electric potential difference (Δψ) during the catalytic cycle of a bd-type triheme terminal quinol oxidase is presented in this work. It is suggested that the main contribution to Δψ formation is made by the movement of H⁺ across the membrane along the intra-protein hydrophilic proton-conducting pathway from the cytoplasm to the active site for oxygen reduction of this bacterial enzyme.

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KEY WORDS: respiratory chain, terminal oxidase, cytochrome bd, heme, protonmotive force, membrane potential

DOI: 10.1134/S0006297923100073

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