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36 degrees step size of proton-driven c-ring rotation in FoF1-ATP synthase.

ABSTRACT: Synthesis of adenosine triphosphate ATP, the 'biological energy currency', is accomplished by F(o)F(1)-ATP synthase. In the plasma membrane of Escherichia coli, proton-driven rotation of a ring of 10 c subunits in the F(o) motor powers catalysis in the F(1) motor. Although F(1) uses 120 degrees stepping during ATP synthesis, models of F(o) predict either an incremental rotation of c subunits in 36 degrees steps or larger step sizes comprising several fast substeps. Using single-molecule fluorescence resonance energy transfer, we provide the first experimental determination of a 36 degrees sequential stepping mode of the c-ring during ATP synthesis.

SUBMITTER: Duser MG

PROVIDER: S-EPMC2750017 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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36 degrees step size of proton-driven c-ring rotation in FoF1-ATP synthase.

Düser Monika G MG Zarrabi Nawid N Cipriano Daniel J DJ Ernst Stefan S Glick Gary D GD Dunn Stanley D SD Börsch Michael M

The EMBO journal 20090730 18

Synthesis of adenosine triphosphate ATP, the 'biological energy currency', is accomplished by F(o)F(1)-ATP synthase. In the plasma membrane of Escherichia coli, proton-driven rotation of a ring of 10 c subunits in the F(o) motor powers catalysis in the F(1) motor. Although F(1) uses 120 degrees stepping during ATP synthesis, models of F(o) predict either an incremental rotation of c subunits in 36 degrees steps or larger step sizes comprising several fast substeps. Using single-molecule fluoresc ...[more]

PMID: 19644443

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