Kinetic modelling of the proton translocating CF0CF1‐ATP synthase from spinach

Abstract
The rate of both ATP synthesis and hydrolysis catalysed by the thiol-modulated and activated ATP synthase from spinach is measured as a function of all substrates including the protons inside the thylakoid lumen. The most important findings are: (1) sigmoid kinetics with respect to Hin +, (2) hyperbolic kinetics with respect to ADP, ATP and phosphate, with K m for phosphate and ADP decreasing upon increasing Hin +, (3) binding of ADP and phosphate in random order and competitive to ATP. Simulation of the complete set of experimental data is obtained by a kinetic model featuring Boyer's binding-change mechanism.