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Tertiary templates for proteins

作者:Jay W. Ponder, Frederic M. Richards · 发表于:Journal of Molecular Biology · 年份:1987 · DOI:10.1016/0022-2836(87)90358-5 · 被引用次数:1492 · 研究领域:Protein Structure and Dynamics、Enzyme Structure and Function、Chemical Synthesis and Analysis

We assume that each class of protein has a core structure that is defined by internal residues, and that the external, solvent-contacting residues contribute to the stability of the structure, are of primary importance to function, but do not determine the architecture of the core portions of the polypeptide chain. An algorithm has been developed to supply a list of permitted sequences of internal residues compatible with a known core structure. This list is referred to as the tertiary template for that structure. In general the positions in the template are not sequentially adjacent and are distributed throughout the polypeptide chain. The template is derived using the fixed positions for the main-chain and beta-carbon atoms in the test structure and selected stereochemical rules. The focus of this paper is on the use of two packing criteria: avoidance of steric overlap and complete filling of available space. The program also notes potential polar group interactions and disulfide bonds as well as possible burial of formal charges. Central to the algorithm is the side-chain rotamer library. In an update of earlier studies by others, we show that 17 of the 20 amino acids (omitting Met, Lys and Arg) can be represented adequately by 67 side-chain rotamers. A list of chi angles and their standard deviations is given. The newer, high-resolution, refined structures in the Brookhaven Protein Data Bank show similar mean chi values, but have much smaller deviations than those of earl...