Torque-Induced Slip of the Rotary Motor F₁-ATPase

Abstract

F(1)-ATPase plays an essential role in cellular metabolism by linking rotational motion to ATP hydrolysis/synthesis. We measure the torque profile of F(1) in both ATP hydrolysis and synthesis directions using a novel magnetic nanorod assay. F(1) is found to decouple ATP synthesis from rotary motion at a surprisingly low torque. This low-torque slip mechanism protects the enzyme from excessive load and may play a broader biological role by reducing the production of reactive oxygen species.