PRIMARY STRUCTURE AND EVOLUTION OF CYTOCHROME C
PRIMARY STRUCTURE AND EVOLUTION OF CYTOCHROME C
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DOI：
10.1073/pnas.50.4.672
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发表时间：
1963-01-01
影响因子：
11.1
通讯作者：
MARGOLIASH, E
中科院分区：
文献类型：
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作者：
MARGOLIASH, E
马、人、猪、兔、鸡、金枪鱼和面包师S酵母细胞色素c的氨基酸序列具有广泛的相似性。这些蛋白质都是进化意义上的同源结构。肽链中的一些残基和序列是不变的，而另一些则是高度可变的。进化对这些蛋白质中显着的碱性残基和疏水残基表现出相当程度的保守性。亲缘关系较近的物种细胞色素c差异不大，而亲缘关系较远的物种细胞色素c差异较大。某些位置上的特定残留物似乎是某些物种或密切相关物种组的特征。仅考虑变异残基的数量，在相对较窄的范围内，某一类的单个物种的蛋白质可能都与另一类的蛋白质一样不同。这种比较的结果与普遍接受的总体进化方案是一致的。各种细胞色素c的初级结构的变异程度可以给出导致任何两个物种的进化线分叉以来所经过的时间的粗略近似。讨论了在这种估计中引入误差的因素。细胞色素c是一种以相对较慢的速度积累突变的蛋白质。蛋白质中氨基酸残基的完全确定的核糖核酸“密码”与一组足够大的同源细胞色素c的氨基酸序列的对抗，可以预期产生沿着一条或多条进化路线的原始细胞色素c的一级结构的估计，以及对在中间、现存或灭绝物种中特定位置发生的特定残基的预测。
The amino acid sequences of the cytochromes c from horse, man, pig, rabbit, chicken, tuna, and baker''s yeast show extensive identities. It is concluded that these proteins are all homologous structures in the evolutionary sense. Some residues and sequences in the peptide chains are invariant, while others are highly variable. Evolution exhibits a considerable degree of conservatism with regard to the remarkable clusters of basic and of hydrophobic residues in these proteins. The cytochromes c from relatively closely related species show few differences, while those from phylogenetically distant species are more widely dissimilar. Particular residues in certain positions appear to be characteristic of certain species or groups of closely related species. Considering only the number of variant residues, the proteins from individual species of one class, within relatively narrow limits, are probably all equally differentf rom those of another. The results of such comparisons are consistentwith the common-ly accepted over-all scheme of evolution. The extent of variation of the pri-mary structure of the various cytochromes c may give rough approximations of the time elapsed since the lines of evolution leading to any two species diverged. The factors introducing errors in such estimates are discussed. Cytochrome c is a protein which has accumulated mutations at a relatively slow rate. The confrontation of completely determined ribonucleic acid "codes" for amino acid residues in proteins with the amino acid sequence of a large enough set of homologous cytochromes c can be expected to yield an estimate of the primary structure of the primordial cytochrome c along one or more lines of evolution, as well as predictions of the particular residues occurring in certain positions in intermediate, extant, or extinct species.