Abstract
Living organisms rely on the FoF1 ATP synthase to maintain the non-equilibrium chemical gradient of ATP to ADP and phosphate that provides the primary energy source for cellular processes. How the Fo motor uses a transmembrane electrochemical ion gradient to create clockwise torque that overcomes F1 ATPase-driven counterclockwise torque at high ATP is a major unresolved question. Using single FoF1 molecules embedded in lipid bilayer nanodiscs, we now report the observation of Fo-dependent rotation of the c10 ring in the ATP synthase (clockwise) direction against the counterclockwise force of ATPase-driven rotation that occurs upon formation of a leash with Fo stator subunit a. Mutational studies indicate that the leash is important for ATP synthase activity and support a mechanism in which residues aGlu-196 and cArg-50 participate in the cytoplasmic proton half-channel to promote leash formation.
Original language | English (US) |
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Pages (from-to) | 10717-10728 |
Number of pages | 12 |
Journal | Journal of Biological Chemistry |
Volume | 290 |
Issue number | 17 |
DOIs | |
State | Published - Apr 24 2015 |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology