细胞色素P450超家族蛋白质基于结构知识的序列联配

应用计算机程序对细胞色素Ｐ４５０蛋白２０个家族的代表序列进行初步多序列联配后，利用结构知识对匹配结果加以调整，调整的依据是Ｐ４５０蛋白二级结构特征和某些超二级结构特征的保守性，三维结构空间配置的保守性，在结构与功能重要残基的保守性，亲水和疏水片段的保守性。大量定点突变实验、选择性化学修饰实验、抗多肽抗体结合实验等能很好地确证该联配结果的正确性。联配结果对真核Ｐ４５０蛋白膜结合方式、活性位点残基分布、与氧化还原偶联蛋白有相互作用的残基的分布等作出了合理的推断。细胞色素Ｐ４５０超家族蛋白基于结构知识的序列联配的尝试对Ｐ４５０蛋白结构与功能关系研究提供了参考

KNOWLEDGE-BASED SEQUENCE ALIGNMENT OF CYTTOCHROMES P450s

The method of knowledge-based sequence alignment of cytochrome P450 proteins was provided on the basis of the conservation of secondary and supersecondary structural motifs, the conservation of three dimensional structures, the conservation of the structurally and functionally important residues, and the conservation of the characteristically hydrophobic and hydrophilic segments. The reliability of the method was confirmed by site-directed mutagenesis, selective chemical modification, site-specific antipeptide antibody binding experiments, and so on. The results of multiple sequence alignment of 20 representative cytochrome P450 protein from different families c reasonably infer the membrane topology, the substrate binding regions and the redox-partner interaction sites. These findings provide the basis for the structure-function studies of cytochrome P450.