驱动蛋白与微管间阳离子-π和π-π的定量分析

The quantitative analysis of the cation-π and π-π between kinesin and microtubule

驱动蛋白是一种ATP酶,属于一种在真核细胞中发现的马达蛋白类.驱动蛋白通过ATP的水解供能,能够沿着微管正向运动.驱动蛋白与微管之间存在着阳离子-π和π-π弱相互作用.用Gaussian软件对驱动蛋白与微管之间的阳离子-π和π-π的能量进行量子化学定量计算.根据计算的数据结果,对阳离子-π和π-π分别做了在ATP强结合态和ADP弱结合态两种态下的统计分析,并得到强结合态和弱结合态在总体上能量相差8.32kJ/mol,表明驱动蛋白处于ATP结合态时与微管的相互作用确实强于ADP结合态,这个结果与有关的实验事实定性地吻合.

Kinesin is a protein belonging to a class of motor proteins found in eukaryotic cells.Kinesins move along microtubule filaments,and are powered by the hydrolysis of ATP.A lot of cation-π and π-π interactions present between motor and tubulin.Gaussian software was used to calculate kinesin＇s binding energy.According to the results,we obtain the quantitative difference in the binding energies for cation-π and π-π interactions between the ATP state and ADP state is 8.32 kJ/mol.This result indicates that the binding strength of kinesin at ATP state is really bigger than that at the ADP state.This result is qualitatively in accordance with experiment.