Professor Masasuke Yoshida
Chemical Resources Laboratory
Tokyo Institute of Technology
Yokohama, Japan

Friday, June 20, 2003
10:00 am (CT)
3269 Beckman Institute

Abstract

ATP synthase can be thought of as a complex of two motors, the ATP-driven F1 motor and the proton-driven Fo motor, that rotate in opposite directions. The mechanisms by which rotation and catalysis are coupled in the working enzyme are being unravelled on a molecular scale by combining results from direct single molecule observations, structural studies by X-ray crystallography and NMR, intersubunit cross-linking, enzyme kinetics, and mutational analysis. Also, two kinds of regulatory mechanisms have been found; one like an engine brake of the car and the other like a disc brake. Apparently violating the second thermodynamic law, both prevent the ATP hydrolysis reaction but not ATP synthesis reaction..