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Ubiquinone Binding and Reduction by Complex I-Open Questions and Mechanistic Implications.

ABSTRACT: NADH: ubiquinone oxidoreductase (complex I) is the first enzyme complex of the respiratory chain. Complex I is a redox-driven proton pump that contributes to the proton motive force that drives ATP synthase. The structure of complex I has been analyzed by x-ray crystallography and electron cryo-microscopy and is now well-described. The ubiquinone (Q) reduction site of complex I is buried in the peripheral arm and a tunnel-like structure is thought to provide access for the hydrophobic substrate from the membrane. Several intermediate binding positions for Q in the tunnel were identified in molecular simulations. Structural data showed the binding of native Q molecules and short chain analogs and inhibitors in the access pathway and in the Q reduction site, respectively. We here review the current knowledge on the interaction of complex I with Q and discuss recent hypothetical models for the coupling mechanism.

SUBMITTER: Galemou Yoga E

PROVIDER: S-EPMC8119997 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Ubiquinone Binding and Reduction by Complex I-Open Questions and Mechanistic Implications.

Galemou Yoga Etienne E Schiller Jonathan J Zickermann Volker V

Frontiers in chemistry 20210430

NADH: ubiquinone oxidoreductase (complex I) is the first enzyme complex of the respiratory chain. Complex I is a redox-driven proton pump that contributes to the proton motive force that drives ATP synthase. The structure of complex I has been analyzed by x-ray crystallography and electron cryo-microscopy and is now well-described. The ubiquinone (Q) reduction site of complex I is buried in the peripheral arm and a tunnel-like structure is thought to provide access for the hydrophobic substrate ...[more]

PMID: 33996767

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