A Generalized Kinetic Model for Coupling between Stepping and ATP Hydrolysis of Kinesin Molecular Motors.
A general kinetic model is presented for the chemomechanical coupling of dimeric kinesin molecular motors with and without extension of their neck linkers (NLs). A peculiar feature of the model is that the rate constants of ATPase activity of a kinesin head are independent of the strain on its NL, implying that the heads of the wild-type kinesin dimer and the mutant with extension of its NLs have the same force-independent rate constants of the ATPase activity. Based on the model, an analytical theory is presented on the force dependence of the dynamics of kinesin dimers with and without extension of their NLs at saturating ATP. With only a few adjustable parameters, diverse available single molecule data on the dynamics of various kinesin dimers, such as wild-type kinesin-1, kinesin-1 with mutated residues in the NLs, kinesin-1 with extension of the NLs and wild-type kinesin-2, under varying force and ATP concentration, can be reproduced very well. Additionally, we compare the power production among different kinesin dimers, showing that the mutation in the NLs reduces the power production and the extension of the NLs further reduces the power production.
['Xie|Ping|P|0000-0003-1485-6355', 'Guo|Si-Kao|SK|', 'Chen|Hong|H|']
D000255:Adenosine Triphosphate D000465:Algorithms D055598:Chemical Phenomena D004789:Enzyme Activation D006868:Hydrolysis D016547:Kinesins D055595:Mechanical Phenomena D008954:Models, Biological D020409:Molecular Motor Proteins
model kinesin molecular motor ATPase activity dynamics mechanochemistry