Chakrabarti P, Pal D
Department of Biochemistry, Bose Institute, P-1/12, CIT Scheme VIIM, 700 054, Calcutta, India. boseinst.ernet.in
Prog Biophys Mol Biol. 2001;76(1-2):1-102. doi: 10.1016/s0079-6107(01)00005-0.
The accurate determination of a large number of protein structures by X-ray crystallography makes it possible to conduct a reliable statistical analysis of the distribution of the main-chain and side-chain conformational angles, how these are dependent on residue type, adjacent residue in the sequence, secondary structure, residue-residue interactions and location at the polypeptide chain termini. The interrelationship between the main-chain (phi, psi) and side-chain (chi 1) torsion angles leads to a classification of amino acid residues that simplify the folding alphabet considerably and can be a guide to the design of new proteins or mutational studies. Analyses of residues occurring with disallowed main-chain conformation or with multiple conformations shed some light on why some residues are less favoured in thermophiles.
通过X射线晶体学准确测定大量蛋白质结构，使得对主链和侧链构象角的分布进行可靠的统计分析成为可能，这些构象角如何依赖于残基类型、序列中的相邻残基、二级结构、残基-残基相互作用以及在多肽链末端的位置。主链（φ、ψ）和侧链（χ1）扭转角之间的相互关系导致了氨基酸残基的分类，这大大简化了折叠字母表，并且可以为新蛋白质的设计或突变研究提供指导。对具有不允许的主链构象或多种构象的残基的分析，揭示了为什么某些残基在嗜热菌中不太受青睐。
