蛋白质折叠速率与其氨基酸序列极性的关系

以大肠杆菌60个蛋白酶以及几种常见病毒（SARS病毒、艾滋病病毒、丙型肝炎病毒及乙型肝炎病毒）各蛋白质序列中的所有α-螺旋和β-折叠片段为研究对象，计算了各片段的折叠速率和平均极性，分别在各物种的α-螺旋和β-折叠两类二级结构片段中分析了二者的相关性。得到结论：不论是大肠杆菌中的蛋白酶还是病毒蛋白，其中的两类氨基酸片段的平均极性与折叠速率都是极显著相关的：对于所有的α片段，二者呈线性正相关，而对于所有的β片段，二者成线性负相关。结果证实了在蛋白质折叠中，氨基酸的极性起着重要的作用。

The relationship between the protein folding rate and its average polarity

The folding rates and the average polarities of segments of α helices and β strands in protease of E coli and those of several kinds of common viruses (SARS, HIV, HCV and HBV) were calculated, and the relationship between the folding rates and the average polarities were analyzed respectively in segments of α helices and β strands. It is found that the folding rates show significantly correlated with the average polarities both for the two kinds of amino acid segments either in the E-coli protease or in the viral protein. For the segments ofα helices, the average polarities shows positive correlation with folding rates,and for the segments of β strands, the average polarities shows negative correlation with fold-rates. It is concluded that the average polarities of amino acid plays an important role in the protein folding.