氨基酸残基可及性与蛋白质家族成员结构的保守性  

AMINO ACID RESIDUE ACCESSIBILITIES AND STRUCTURAL CONSERVATIVENESS OF MOLECULES IN PROTEIN FAMILY

作　　者：黄京飞[1] 刘次全[1] 

机构地区：[1]中国科学院昆明动物研究所细胞与分子进化开放研究实验室

出　　处：《Zoological Research》1998年第2期137-142,共6页动物学研究（英文）

基　　金：云南省应用基础科学研究基金

摘　　要：本文在细胞色素ｃ族蛋白和免疫球蛋白家族中一些蛋白质片段的序列比较和分析的基础上，通过计算其氨基酸残基的可及性，对残基可及性与蛋白质序列及其三维结构的保守性之间的关系进行了分析和探讨。结果表明，序列中凡是保守的残基，其可及性都较低，而且这些低可及性的保守性残基与维持蛋白质特有的三维结构相关。作者认为，同一家族的蛋白质中，在进化上相距较远的各成员之间，结构的保守性主要是体现在其三维结构上；序列中的保守性残基，对于维持整个蛋白质分子特定的三维结构和功能有着重要的意义；此外，序列中的保守性残基一般均位于其整个分子结构的内部，因而具有较低的可及性。鉴于“可及性”本身只具有相对的意义，故可及性较低的残基不一定是保守的，而保守的残基则是低可及性的。おased on the comparison and analysis on the sequences of cytochrome c family and some domain fragments in immunoglobulin family,the protein amino acid residue accessibilities have been calculated,and the relationship between amino acid residue accessibilities,protein sequences' and three-dimensional structural conservativeness has been analyzed and discussed. The results indicated that all conserved residues in sequences have lower accessibilities,and the conserved residues with lower accessibilities are close correlative to keeping protein specific threedimensional structures. It is suggested that protein structural conservativeness is mainly expressed in their three-dimensional structures between evolutionary distant various protein molecules within families of proteins,and the conserved residues in sequences play an important role to keep specific three-dimensional structure in whole protein molecule. In addition,it is found that the conserved residues in sequences are generally located in the interior of whole protein molecular structure. This is why their accessibilities are lower. Of course,not all lower accessible residues are conserved,but the conserved residues are those with lower accessibilities.

关 键 词：残基 可及性 蛋白质家族 结构保守性 氨基酸 

分 类 号：Q517[生物学—生物化学]