Ghosh I, McCammon J A
Biophys J. 1987 Apr;51(4):637-41. doi: 10.1016/S0006-3495(87)83388-X.
Molecular dynamics simulations are used to study the rotational isomerization of the tyrosine 35 ring in bovine pancreatic trypsin inhibitor immersed in liquid water. Inclusion of the solvent surroundings improves the agreement with experimental results significantly, although the theoretical free energy barrier (13 kcal/mol at 300K) is still approximately 3 kcal/mol below that found by nuclear magnetic resonance studies. This remaining discrepancy will probably be eliminated in future calculations by the use of a more accurate model for the hydrogen atoms on the tyrosine ring. An important finding in the present work is that frictional effects due to solvent damping appear to be small for the tyrosine 35 ring, which is largely but not completely buried in the protein surface.
分子动力学模拟用于研究浸入液态水中的牛胰蛋白酶抑制剂中酪氨酸35环的旋转异构化。尽管理论自由能垒（300K时为13千卡/摩尔）仍比核磁共振研究结果低约3千卡/摩尔，但包含溶剂环境显著改善了与实验结果的一致性。通过使用更精确的酪氨酸环上氢原子模型，未来的计算可能会消除这一剩余差异。本研究的一个重要发现是，对于主要但并非完全埋在蛋白质表面的酪氨酸35环，溶剂阻尼引起的摩擦效应似乎很小。
