Solvent Exposure Imparts Similar Selective Pressures across a Range of Yeast Proteins
Solvent Exposure Imparts Similar Selective Pressures across a Range of Yeast Proteins
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DOI：
10.1093/molbev/msp031
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发表时间：
2009-05-01
影响因子：
10.7
通讯作者：
Stadler, Peter F.
中科院分区：
文献类型：
--
作者：
Conant, Gavin C.;Stadler, Peter F.
我们研究了如何氨基酸残基的溶剂暴露影响其倾向的取代通过分析61酵母基因的晶体结构是已知的多重比对。我们发现，内部残留物的选择性约束是平均10倍，残留物的表面上。令人惊讶的是，在蛋白质比对观察到的总体选择性约束与内部和表面残基上的约束的比率之间没有相关性。通过对几种氨基酸性质的选择性约束进行建模，我们表明，虽然残基体积和亲水性在大多数比对中是强烈保守的，但这两种性质的内部与表面保守性的变化很小。相比之下，残基电荷（等电点）一般不太保守，当考虑作为一个整体的蛋白质，但显示了强大的约束，对引入带电残基到蛋白质内部。
We study how an amino acid residue's solvent exposure influences its propensity for substitution by analyzing multiple alignments of 61 yeast genes for which the crystal structure is known. We find that the selective constraint on the interior residues is on average 10 times that of residues on the surface. Surprisingly, there is no correlation between the overall selective constraint observed for a protein alignment and the ratio of constraints on interior and surface residues. By modeling the selective constraint on several amino acid properties, we show that although residue volume and hydropathy are strongly conserved across most alignments, there is little variation in interior versus surface conservation for these two properties. By contrast, residue charge (isoelectric point) is less generally conserved when considering the protein as a whole but shows a strong constraint against the introduction of charged residues into the protein interior.