title: Single molecule Michaelis-Menten equation beyond quasistatic disorder.
abstract: The classic Michaelis-Menten equation describes the catalytic activities for ensembles of enzyme molecules very well. But recent single-molecule experiments showed that the waiting time distribution and other properties of single enzyme molecules were not consistent with the prediction based on the ensemble viewpoint. They have contributed to the slow conformational changes of a single enzyme in the catalytic processes. In this work, we study the general dynamics of single enzymes in the presence of dynamic disorder. We find that, within the time separation regimes, i.e., the slow reaction and nondiffusion limits, the Michaelis-Menten equation holds exactly. In particular, by employing the decoupling approximation we demonstrate analytically that the classic Michaelis-Menten equation is still an excellent approximation in the presence of general dynamic disorder.
authors.affiliation: Center for Advanced Study, Tsinghua University, Beijing 100084, China.
authors.forename: Xiaochuan
authors.initials: X
authors.lastname: Xue
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Zhong-Can
authors.initials: ZC
authors.lastname: Ou-Yang
mesh_terms: D002384:Catalysis; D003198:Computer Simulation; D004798:Enzymes / Q000378:metabolism*; D007700:Kinetics; D008954:Models, Biological; D013379:Substrate Specificity
chemical_list: D004798:Enzymes