Model for the fast estimation of basis set superposition error in biomolecular systems.
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.
Quantum Theory Project, The University of Florida, 2328 New Physics Building, P.O. Box 118435, Gainesville, Florida 32611-8435, USA.
John C
JC
Faver
Zheng
Z
Zheng
Kenneth M
KM
Merz
D008958:Models, Molecular; D015233:Models, Statistical; D019696:Peptidylprolyl Isomerase / Q000737:chemistry; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics
D011506:Proteins; D019696:Peptidylprolyl Isomerase