A Theory for Rate Constants in Rotation Trajectories of F1-ATPase

Abstract

I present an elastic chemo-mechanical theory to treat single molecule imaging and “stalling” experiments in the F1-ATPase enzyme. Using a molecular group transfer approach the theory couples chemical reactions in the stator and the physics of torsional elasticity in the rotor. In the theory we predicted and compared with experiment the rate and equilibrium constant dependence of steps such as ATP binding as a function of the rotor angle.[PNAS, 112, 14230 (2015)] Using independent experimental data from biochemical ensemble and single-molecule imaging experiments, the model correctly predicts the controlled rotation data on fluorescent ATP without any adjustable parameters. We took into account the biasing effect of finite experimental time resolution in the single fluorescence trajectories and treated these data by developing computational statistical methods.[PNAS, 113 (48), 12029 (2016)] A theory-based method for the extraction of rate constants for hydrolysis and synthesis from controlled rotation data was also provided for angular range where no such data is currently available [PNAS, 114, 7272 (2016)] The framework is generic and we plan to apply it to other biomolecular motors.