Affinity of small ligands to myoglobin studied by the 3D-RISM theory

作者:Kiyota Yasuomi; Yoshida Norio; Hirata Fumio*
来源:Journal of Molecular Liquids, 2011, 159(1): 93-98.
DOI:10.1016/j.molliq.2010.07.016

摘要

The affinity of small ligands including O(2), Xe, NO, CO, H(2)S, and H(2)O to myoglobin is studied based on the Three-dimensional Reference Interaction Site Model (3D-RISM) theory, the statistical mechanics of molecular liquids. The affinity is evaluated in terms of the coordination number of ligands in cavities in the protein, or the "Xe site," which can be obtained from the radial distribution function of ligand molecules inside the cavities. It is found that NO, CO, and H(2)S show greater affinity to the Xe sites than O(2) does, while the affinity of Xe is lower than that of O(2). A relevance of the results to the physiological activity of the protein is speculated. The physical origin of the difference in affinity among the ligands is discussed.

  • 出版日期2011-2-15