Title

36 Degrees Step Size of Proton-driven C-ring Rotation in FoF1-ATP Synthase

Document Type

Article

Publication Date

9-16-2009

Journal

EMBO Journal

Volume

28

Issue

18

First Page

2689

Last Page

2696

URL with Digital Object Identifier

10.1038/emboj.2009.213

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.