J. Stefan Institute , Jamova 39, 1000 Ljubljana , Slovenia ; Faculty of Mathematics and Physics , University of Ljubljana , Jadranska 19, 1000 Ljubljana , Slovenia.
Interface Focus. 2014 Dec 6;4(6):20140032. doi: 10.1098/rsfs.2014.0032.
We study the ensemble velocity of non-processive motor proteins, described with multiple chemical states. In particular, we discuss the velocity as a function of ATP concentration. Even a simple model which neglects the strain dependence of transition rates, reverse transition rates and nonlinearities in the elasticity can show interesting functional dependencies, which deviate significantly from the frequently assumed Michaelis-Menten form. We discuss how the order of events in the duty cycle can be inferred from the measured dependence. The model also predicts the possibility of velocity reversal at a certain ATP concentration if the duty cycle contains several conformational changes of opposite directionalities.
我们研究了具有多种化学状态的非进行性马达蛋白的整体速度。特别是，我们讨论了速度作为 ATP 浓度的函数。即使是一个简单的模型，忽略了转变率、反向转变率和弹性中的非线性对应变的依赖性，也可以显示出有趣的功能依赖性，这些依赖性与经常假设的米氏-门登形式有很大的不同。我们讨论了如何从测量的依赖性中推断出作用循环中事件的顺序。如果作用循环包含几个相反方向的构象变化，则该模型还预测了在特定 ATP 浓度下速度反转的可能性。
