Fajer Mikolai, Swift Robert V, McCammon J Andrew
Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, California 92093-0365, USA.
J Comput Chem. 2009 Aug;30(11):1719-25. doi: 10.1002/jcc.21285.
Replica exchange accelerated molecular dynamics (REXAMD) is a method that enhances conformational sampling while retaining at least one replica on the original potential, thus avoiding the statistical problems of exponential reweighting. In this article, we study three methods that can combine the data from the accelerated replicas to enhance the estimate of properties on the original potential: weighted histogram analysis method (WHAM), pairwise multistate Bennett acceptance ratio (PBAR), and multistate Bennett acceptance ratio (MBAR). We show that the method that makes the most efficient use of equilibrium data from REXAMD simulations is the MBAR method. This observation holds for both alchemical free energy and structural observable prediction. The combination of REXAMD and MBAR should allow for more efficient scaling of the REXAMD method to larger biopolymer systems.
复制交换加速分子动力学(REXAMD)是一种在原始势能上至少保留一个副本的同时增强构象采样的方法,从而避免了指数重加权的统计问题。在本文中,我们研究了三种可以结合加速副本数据以增强对原始势能性质估计的方法:加权直方图分析方法(WHAM)、成对多态贝内特接受率(PBAR)和多态贝内特接受率(MBAR)。我们表明,最有效地利用REXAMD模拟平衡数据的方法是MBAR方法。这一观察结果在炼金术自由能和结构可观测量预测方面均成立。REXAMD和MBAR的结合应能使REXAMD方法更有效地扩展到更大的生物聚合物系统。