Development of a partial simulation method of proteins based on all-electron calculations

Abstract

To reveal functions of proteins, it is important to understand dynamical features of proteins. Especially in biocatalyst processes, quantum chemical calculations are indispensable. We developed a Gaussian-based density functional method program, ProteinDF, and achieved the all-electron calculations on proteins. However, the protein dynamics simulation based on all-electron calculation is still far from a practical idea in a present computer resource. To overcome this problem, we also developed a new method to calculate localized molecular orbitals on fragments. We named it quasi-canonical localized orbital (QCLO) method. By using this method, we can perform partial simulations of proteins based on all-electron calculations to divide into the dynamically and statically calculated areas, which greatly decrease the computational task. In this study, we implemented the partial simulation program using the QCLO method. We will discuss the details of the computational method and show the effectiveness of this method.