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High-resolution cryo-EM analysis of the yeast ATP synthase in a lipid membrane.

ABSTRACT: Mitochondrial adenosine triphosphate (ATP) synthase comprises a membrane embedded Fo motor that rotates to drive ATP synthesis in the F1 subunit. We used single-particle cryo-electron microscopy (cryo-EM) to obtain structures of the full complex in a lipid bilayer in the absence or presence of the inhibitor oligomycin at 3.6- and 3.8-angstrom resolution, respectively. To limit conformational heterogeneity, we locked the rotor in a single conformation by fusing the F6 subunit of the stator with the ? subunit of the rotor. Assembly of the enzyme with the F6-? fusion caused a twisting of the rotor and a 9° rotation of the Fo c10-ring in the direction of ATP synthesis, relative to the structure of isolated Fo Our cryo-EM structures show how F1 and Fo are coupled, give insight into the proton translocation pathway, and show how oligomycin blocks ATP synthesis.

SUBMITTER: Srivastava AP

PROVIDER: S-EPMC5948177 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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High-resolution cryo-EM analysis of the yeast ATP synthase in a lipid membrane.

Srivastava Anurag P AP Luo Min M Zhou Wenchang W Symersky Jindrich J Bai Dongyang D Chambers Melissa G MG Faraldo-Gómez José D JD Liao Maofu M Mueller David M DM

Science (New York, N.Y.) 20180412 6389

Mitochondrial adenosine triphosphate (ATP) synthase comprises a membrane embedded Fo motor that rotates to drive ATP synthesis in the F1 subunit. We used single-particle cryo-electron microscopy (cryo-EM) to obtain structures of the full complex in a lipid bilayer in the absence or presence of the inhibitor oligomycin at 3.6- and 3.8-angstrom resolution, respectively. To limit conformational heterogeneity, we locked the rotor in a single conformation by fusing the F6 subuni ...[more]

PMID: 29650704

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