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How cardiolipin modulates the dynamics of respiratory complex I.

ABSTRACT: Cardiolipin modulates the activity of membrane-bound respiratory enzymes that catalyze biological energy transduction. The respiratory complex I functions as the primary redox-driven proton pump in mitochondrial and bacterial respiratory chains, and its activity is strongly enhanced by cardiolipin. However, despite recent advances in the structural biology of complex I, cardiolipin-specific interaction mechanisms currently remain unknown. On the basis of millisecond molecular simulations, we suggest that cardiolipin binds to proton-pumping subunits of complex I and induces global conformational changes that modulate the accessibility of the quinone substrate to the enzyme. Our findings provide key information on the coupling between complex I dynamics and activity and suggest how biological membranes modulate the structure and activity of proteins.

SUBMITTER: Jussupow A

PROVIDER: S-EPMC6426460 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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How cardiolipin modulates the dynamics of respiratory complex I.

Jussupow Alexander A Di Luca Andrea A Kaila Ville R I VRI

Science advances 20190320 3

Cardiolipin modulates the activity of membrane-bound respiratory enzymes that catalyze biological energy transduction. The respiratory complex I functions as the primary redox-driven proton pump in mitochondrial and bacterial respiratory chains, and its activity is strongly enhanced by cardiolipin. However, despite recent advances in the structural biology of complex I, cardiolipin-specific interaction mechanisms currently remain unknown. On the basis of millisecond molecular simulations, we sug ...[more]

PMID: 30906865

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