Quantum Theory Project, The University of Florida, 2328 New Physics Building, P.O. Box 118435, Gainesville, Florida 32611-8435, USA.
J Chem Phys. 2011 Oct 14;135(14):144110. doi: 10.1063/1.3641894.
Basis set superposition error (BSSE) is a significant contributor to errors in quantum-based energy functions, especially for large chemical systems with many molecular contacts such as folded proteins and protein-ligand complexes. While the counterpoise method has become a standard procedure for correcting intermolecular BSSE, most current approaches to correcting intramolecular BSSE are simply fragment-based analogues of the counterpoise method which require many (two times the number of fragments) additional quantum calculations in their application. We propose that magnitudes of both forms of BSSE can be quickly estimated by dividing a system into interacting fragments, estimating each fragment's contribution to the overall BSSE with a simple statistical model, and then propagating these errors throughout the entire system. Such a method requires no additional quantum calculations, but rather only an analysis of the system's interacting fragments. The method is described herein and is applied to a protein-ligand system, a small helical protein, and a set of native and decoy protein folds.
基组叠加误差（BSSE）是量子基能量函数误差的主要贡献者，特别是对于具有许多分子接触的大型化学系统，例如折叠蛋白质和蛋白质-配体复合物。虽然平衡校正法已成为校正分子间 BSSE 的标准程序，但目前大多数校正分子内 BSSE 的方法只是平衡校正法的基于片段的类似方法，在应用中需要进行许多（片段数目的两倍）额外的量子计算。我们提出，通过将系统划分为相互作用的片段，可以快速估计两种形式的 BSSE 的大小，用简单的统计模型估算每个片段对整体 BSSE 的贡献，然后将这些误差传播到整个系统中。该方法不需要额外的量子计算，而只需对系统的相互作用片段进行分析。本文介绍了该方法，并将其应用于蛋白质-配体系统、一个小螺旋蛋白质以及一组天然和诱饵蛋白质折叠。
