血红素近轴侧基氢键的ABEEM/MM分子动力学模拟

Dynamic Simulations of the Hydrogen-bondings on the Proximal Side of the Heme in Terms of ABEEM/MM Method

应用ABEEM/MM浮动电荷力场对鲸鱼肌红蛋白及突变体进行了分子动力学模拟.结果表明,血红素近轴侧基不存在稳定的双氢键,该氢键对轴配体咪唑的取向不起决定性作用,而咪唑的取向与键联的组氨酸有密切联系.同时表明,血红素轴配体的柔性与其邻近的氨基酸和咪唑体积有关.

The structures of sperm whale myoglobin（Mb）and mutants were investigated in terms of the ABEEM/MM method.The molecular dynamic simulations showed that the bifurcated hydrogen-bondings in the proximal side of the heine in Mb were not stable.These simulations indicated that hydrogen-bondings could not determine the overall orientation of imidazole,which could be related to the histidine residue.The amide acids and the bulk of the imidazole can have effects on the flexibility of proximal ligands.