以分子动力学模拟探究苹果酸脱氢酶的嗜极机制

Molecular dynamics simulations of malate dehydrogenase to explore extremophiles mechanism

为了研究嗜热酶、嗜冷酶在极端温度下维持稳定性和活性的机制,本文通过分子动力学模拟的方法,从原子尺度上分析了嗜热苹果酸脱氢酶及其同源嗜冷酶的分子动力学特性。数据显示嗜热酶所形成的盐桥和氢键明显多于嗜冷酶。通过比较均方根偏差、回旋半径、氨基酸残基的柔性等值,发现嗜热酶的结构较非嗜热酶更具刚性。盐桥、氢键数目的不同和整体结构的刚柔性,很可能会是嗜热、嗜冷酶在极端温度下能维持结构稳定的主要原因。

In order to explore the properties of thermophilic enzyme and psychrophilic enzyme further, this paper use molecular dynamics simulation to analysis malate dehydrogenase in atomic scale. The results found that, thermophilic enzyme can form more salt bridges and hydrogen bonds than the psychrophilic enzymes. By comparing the root mean square deviation, radius of gyration and end distance equivalent, we also found the structure of thermophilic enzyme is more rigid. The flexible of two amino acids residues of thermophilic enzyme is larger. Forming more hydrogen bonds and salt bridges and the rigidity of the whole structure is likely to be the main reason that thermophilic enzyme maintain its stability structure in high temperature.