paper

Single molecule thermodynamics of ATP synthesis by F-ATPase

arXiv:1210.4017 · doi:10.1088/1367-2630/17/1/015008

Abstract

FF-ATP synthase is a factory for synthesizing ATP in virtually all cells. Its core machinery is the subcomplex F-motor (F-ATPase) and performs the reversible mechanochemical coupling. Isolated F-motor hydrolyzes ATP, which is accompanied by unidirectional rotation of its central -shaft. When a strong opposing torque is imposed, the -shaft rotates in the opposite direction and drives the F-motor to synthesize ATP. This mechanical-to-chemical free-energy transduction is the final and central step of the multistep cellular ATP-synthetic pathway. Here, we determined the amount of mechanical work exploited by the F-motor to synthesize an ATP molecule during forced rotations using methodology combining a nonequilibrium theory and single molecule measurements of responses to external torque. We found that the internal dissipation of the motor is negligible even during rotations far from a quasistatic process.

10 pages, 4 figures

References in corpus (2)

Cited by in corpus (11)