高压诱导小蛋白Chignoli变性的分子动力学研究

Molecular Dynamical Study of High Pressure Induced Miniprotein Chignolin Denaturation

在温度为300K,压强为200、1000和2000MPa时,分别对小蛋白Chignolin进行了50ns的分子动力学模拟,模拟中考虑了水的压缩性系数随压强的改变情况.结果表明,在高压下Chignolin的构象产生非常显著的变化,出现了完全去折叠.通过研究水和Chignolin之间氢键作用发现,两者之间的氢键数目变化趋势与蛋白质构象变化相一致.进一步研究还发现,压强的增大还会抑制Chignolin的去折叠;同时对高压诱导小蛋白变性的机理进行了分析.

The molecular dynamical simulation has been performed for the miniprotein Chignolin under the pressure of 200, 1 000 and 2 000 MPa at the temperature of 300 K. In the simulation, the changes of the compressibility of water along with the pressure are considered. The results show that at high pressure, the conformation of Chignolin changes remarkably, and complete unfolding appears. Through studying the hydrogen bond between water and Chignohn, the authors find that the variation trend of hydrogen-bond number is just the same as that of protein conformations. The further study shows that the increase of pressure will inhibit the unfolding of Cbignolin. Based on these, the mechanism of Chignolin denatruation is also studied.