Department of Mechanical Engineering, Korea University, Seoul 136-701, Republic of Korea.
J Chem Phys. 2012 Jul 14;137(2):025102. doi: 10.1063/1.4732798.
Single-molecule mechanical manipulation has enabled quantitative understanding of not only the kinetics of both bond rupture and protein unfolding, but also the free energy landscape of chemical bond and/or protein folding. Despite recent studies reporting the role of loading device in bond rupture, a loading device effect on protein unfolding mechanics has not been well studied. In this work, we have studied the effect of loading-device stiffness on the kinetics of both bond rupture and protein unfolding mechanics using Brownian dynamics simulations. It is shown that bond rupture forces are dependent on not only loading rate but also the stiffness of loading device, and that protein unfolding mechanics is highly correlated with the stiffness of loading device. Our study sheds light on the importance of loading device effect on the mechanically induced bond ruptures and protein unfolding.
单分子力学操纵不仅使人们能够定量理解键断裂和蛋白质展开的动力学，还使人们能够定量理解化学键和/或蛋白质折叠的自由能景观。尽管最近的研究报告了加载装置在键断裂中的作用，但加载装置对蛋白质展开力学的影响尚未得到很好的研究。在这项工作中，我们使用布朗动力学模拟研究了加载装置刚度对键断裂动力学和蛋白质展开力学的影响。结果表明，键断裂力不仅取决于加载速率，还取决于加载装置的刚度，并且蛋白质展开力学与加载装置的刚度高度相关。我们的研究揭示了加载装置效应对机械诱导键断裂和蛋白质展开的重要性。
