实验表明水的压缩系数随着压强的改变会发生变化,这种改变将对高压致蛋白质变性的充分含水动力学模拟结果产生直接影响,然而很多高压变性的分子动力学模拟并没有考虑这一点.在温度为300 K,压强为200 MPa、1000 MPa时,利用GROMACS软件包对两种小蛋白Chignolin和Trpcage进行了总计300ns的分子动力学模拟,模拟中考虑了水的压缩系数随压强的改变情况,然后将模拟结果与压缩系数维持在0.1 MPa时的情况进行了比较.结果发现,压缩系数对蛋白质高压变性的影响很大,依据实验数据对不同压强的压缩系数进行调整后,小蛋白Chignolin在高压变性中出现完全去折叠.这为分子动力学模拟研究蛋白质高压变性提供了正确的途径和理论依据.
The compressibility changes along with the pressure which can infulence the results of MD simulation of high pressure induced protein denaturation using the SPC/E model, while some works have ignored this. In this paper, the MD simulation was runned by using Gromaes software to study the high pressure induced unfolding of miniprotein Chignolin and Trpcage at 300 K and 200 MPa, 1000 MPa, the total simulation time add up to 300 nano seconds and the change of compressibility of water with pressure was considered. The results show that the compressibility influence the unfolding greatly, the protein Chignolin even all unfolded after modifing the compressibility according to the pressure. These have provided correct ways and theoretieal basis for MD simulate high pressure induced protein denaturation.