Catalytic robustness and torque generation of the F1-ATPase

The F 1 -ATPase is the catalytic portion of the F o F 1 ATP synthase and acts as a rotary molecular motor when it hydrolyzes ATP. Two decades have passed since the single-molecule rotation assay of F 1 -ATPase was established. Although several fundamental issues remain elusive, basic properties of F-type ATPases as motor proteins have been well characterized, and a large part of the reaction scheme has been revealed by the combination of extensive structural, biochemical, biophysical, and theoretical studies. This review is intended to provide a concise summary of the fundamental features of F 1 -ATPases, by use of the well-described model F 1 from the thermophilic Bacillus PS3 (TF 1 ). In the last part of this review, we focus on the robustness of the rotary catalysis of F 1 -ATPase to provide a perspective on the re-designing of novel molecular machines.