Ofran Yanay, Margalit Hanah
CUBIC, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.
Proteins. 2006 Jul 1;64(1):275-9. doi: 10.1002/prot.20964.
It is well established that there is a relationship between the amino acid composition of a protein and its structural class (i.e., alpha, beta, alpha + beta, or alpha/beta). Several studies have even shown the power of amino acid composition in predicting the secondary structure class of a protein. Herein, we show that significant similarity in amino acid composition exists not only between proteins of the same class, but even between proteins of the same fold. To test conjectural explanations for this phenomenon, we analyzed a set of structurally similar proteins that are dissimilar in sequence. Based on this analysis, we suggest that specific residues that are involved in intramolecular interactions may account for this surprising relationship between composition and structure.
蛋白质的氨基酸组成与其结构类别（即α、β、α + β或α/β）之间存在关联，这一点已得到充分证实。多项研究甚至表明，氨基酸组成在预测蛋白质二级结构类别方面具有强大作用。在此，我们表明，不仅同一类别的蛋白质之间存在氨基酸组成的显著相似性，甚至同一折叠类型的蛋白质之间也存在这种相似性。为了检验对这一现象的推测性解释，我们分析了一组序列不同但结构相似的蛋白质。基于这一分析，我们认为参与分子内相互作用的特定残基可能是造成组成与结构之间这种惊人关系的原因。
