论文标题
有限尺寸效应和蛋白质折叠的两态范例
The finite size effects and the two-state paradigm of protein folding
论文作者
论文摘要
多肽链向球旋转的线圈是球状蛋白折叠背后的物理现象。具有单个结构域的球状蛋白通常由约30至100个氨基酸残基组成，并且该有限的大小扩展了线圈圆锥形相变的过渡间隔。基于两态模型的登记推导，我们介绍了多肽链的氨基酸残基的数量，作为两种协同度量的表达式中的参数，并揭示了它们的身体意义。我们得出的结论是，$ k_2 $衡量标准与变性状态的堕落有关，描述了涉及过渡的合作单位的数量；此外，发现著名的条件$ k_2 = 1 $只是将蛋白质分类为两态文件夹的必要条件。我们还发现$ω_c$与过渡间隔的平方成正比。这一事实使我们能够对线圈球相变的经典尺寸缩放分析。此外，这两种措施被证明描述了蛋白质折叠的不同特征。
The coil to globule transition of the polypeptide chain is the physical phenomenon behind the folding of globular proteins. Globular proteins with a single domain usually consist of about 30 to 100 amino acid residues, and this finite size extends the transition interval of the coil-globule phase transition. Based on the pedantic derivation of the two-state model, we introduce the number of amino acid residues of a polypeptide chain as a parameter in the expressions for two cooperativity measures and reveal their physical significance. We conclude that the $k_2$ measure, related to the degeneracy of the denatured state, describes the number of cooperative units involved in the transition; additionally is found that the famous condition $k_2=1$ is just the necessary condition to classify the protein as the two-state folder. We also find that $Ω_c$ is simply proportional to the square of the transition interval. This fact allows us to perform the classical size scaling analysis of the coil-globule phase transition. Moreover, these two measures are shown to describe different characteristics of protein folding.
