以分子动力组学的方法探究嗜盐酶的嗜盐机理

Halophilic Mechanism of the Halophilic Enzymes Based on the Molecule Dynameomics Method

通过分子动力组学的方法,从原子尺度上分析4组嗜盐酶及其同源非嗜盐酶的分子动力学特性.结果发现:嗜盐酶所形成的盐桥和氢键明显多于非嗜盐酶,嗜盐酶的溶剂可及性表面要小于非嗜盐酶.通过比较嗜盐与非嗜盐的均方根偏差、回旋半径及末端距等参数,发现嗜盐酶的结构较非嗜盐酶更具刚性.同时,非嗜盐酶多个部位的氨基酸残基柔性比嗜盐酶的要大很多.研究表明:能形成较多的盐桥、氢键,较小的溶剂可及性表面和整体结构的刚性,很可能是嗜盐酶在高盐环境中维持其结构稳定的主要原因.

We analyzed the dynamics characteristics of the four groups halophilic enzyme and non-halophilic homologs by molecule dynameornics method in the atomistic scale. The results found that： halophilic enzyme can form more salt bridg- es and hydrogen bonds than non-halophilic enzyme, the solvent accessible surface areas of halophilic enzyme are larger than non-halophilic enzym We also found that the structure of halophilic enzyme is more rigid by comparing the root mean square deviation （RMSD）, radius of gyration and end distance. Besides, the flexibility of the amino acids of nonhalophilic enzyme is more large than halophilic enzym It can be supposed that the main factors that halophilic enzymes can maintain their structure stability in high saline conditions are rich in salt bridges and hydrogen bonds, smaller solvent accessible surface area and structure rigidity.