School of Chemistry, Damghan University, Damghan, Iran.
Protein J. 2021 Feb;40(1):1-7. doi: 10.1007/s10930-020-09961-6. Epub 2021 Jan 14.
One of the most important steps in modeling three-dimensional (3D) structures of proteins is the evaluation of the constructed models. The present study suggests that the correctness of a structure may be tested by using the characteristics of sequential dihedral angles (SDAs) between adjacent alpha-carbons (C) in the main chains of proteins. From our studies on protein structures in the protein data bank (PDB), the SDAs between the C in the main chains are limited in their values. In addition, the sum of the absolute values of the three sequential dihedral angles (SDAs) can never be 0 degree. Moreover, 48 degrees is the lowest value existing for the sum of the absolute values of three sequential dihedral angles (SDAs). Thus, the SDAs between the alpha-carbons along the main chains of proteins may be a useful parameter for evaluating anomalies in protein structures.
在构建蛋白质的三维（3D）结构的最重要步骤之一是对构建模型进行评估。本研究表明，可以通过使用蛋白质主链中相邻α-碳原子（C）之间的顺序二面角（SDA）的特征来测试结构的正确性。从我们对蛋白质数据库（PDB）中蛋白质结构的研究中可以发现，主链中 C 之间的 SDA 值是有限的。此外，三个连续二面角（SDA）的绝对值之和永远不可能为 0 度。此外，三个连续二面角（SDA）的绝对值之和的最小值为 48 度。因此，蛋白质主链中α-碳原子之间的 SDA 可能是评估蛋白质结构异常的有用参数。
