Sechenykh A A, Dubanov A V, Skvortsov V S, Ivanov A S, Archakov A I, Williams P, Cosme J, Johnson E F, McRee D E
Orekhovich Institute of Biomedical Chemistry RAMS, 10, Pogodinskaya str., Moscow, 119121, Russia.
Vopr Med Khim. 2002 Sep-Oct;48(5):526-38.
Cytochromes P450 (CYPs) play an important role in the oxidative metabolism of xenobiotics. Three-dimensional structures of CYPs are needed to study structure-function relationships in their molecules and interaction with partner proteins. Experimental determination of eucaryotic CYPs 3D structures is difficult because of hydrophobic membrane anchors and surface hydrophobic regions that prevent their crystallization. Replacement of surface hydrophobic amino acids by hydrophilic residues without any changes in protein structure and function can help to solve this problem. Such modification can be proposed using the analysis of 3D model of protein. In this work computer aided 3D structure of microsomal P450 2B4 (CYP2B4) was modeled for the further prediction of surface mutations for hydrophilization of the protein surface. The model of 3D structure of CYP2B4 was constructed by homology with CYP2C5 Model optimization was made by energy minimization and molecular dynamics simulation of protein molecule in water environment. The model was verified by using special statistic software and by comparison with the experimental data on the substrate recognition site, redox-partner binding sites and chemical modification of the protein surface.
细胞色素P450(CYPs)在异生素的氧化代谢中发挥着重要作用。需要细胞色素P450的三维结构来研究其分子中的结构-功能关系以及与伴侣蛋白的相互作用。由于疏水性膜锚和表面疏水区域会阻止真核细胞色素P450的结晶,因此其实验三维结构的测定较为困难。用亲水性残基取代表面疏水性氨基酸而不改变蛋白质的结构和功能,有助于解决这一问题。可以通过分析蛋白质的三维模型来提出这种修饰方法。在这项工作中,对微粒体P450 2B4(CYP2B4)的计算机辅助三维结构进行了建模,以便进一步预测蛋白质表面亲水化的表面突变。通过与CYP2C5的同源性构建了CYP2B4的三维结构模型,并通过能量最小化和蛋白质分子在水环境中的分子动力学模拟对模型进行了优化。通过使用特殊的统计软件并与底物识别位点、氧化还原伴侣结合位点以及蛋白质表面化学修饰的实验数据进行比较,对该模型进行了验证。