BETA-BREAKERS - AN APERIODIC SECONDARY STRUCTURE
BETA-BREAKERS - AN APERIODIC SECONDARY STRUCTURE
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DOI：
10.1016/0022-2836(91)80075-6
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发表时间：
1991-09-20
影响因子：
5.6
通讯作者：
COHEN, FE
中科院分区：
文献类型：
--
作者：
COLLOCH, N;COHEN, FE
我们研究了蛋白质中平行β-片的结构，并重点研究了启动和终止β-链的残基。这些β破环残基位于β链之间扭结的起点，以及在它之前或之后的转弯处。利用基于算法二级结构分配、溶剂可及性和主二面角的共识方法，可以自动定位β-破坏者。在侧链溶剂可及性和主二面角分布方面，这些β-破片构象是均匀的。一个序列-结构的相关性被注意到：在这些位置上观察到一个有限的氨基酸子集。同源蛋白序列分析表明，这些残基比环内其他残基保守性更高。我们得出结论，β-破片是α-螺旋的N端和c端帽的结构类似物。这种非周期亚结构的识别为改进二级结构预测提供了一种策略，并可能指导定点诱变实验。
We have studied the architecture of parallel β-sheets in proteins and focused on the residues that initiate and terminate the β-strands. These β-breaker residues are at the origin of the kink between the β-strand and the turn that precedes or follows it. β-Breakers can be located automatically using a consensus approach based on algorithmic secondary structure assignment, solvent accessibility and backbone dihedral angles. These β-breakers are conformationally homogeneous with respect to side-chain solvent accessibility and backbone dihedral angle profile. A sequence-structure correlation is noted: a restricted subset of amino acids is observed at these positions. Analysis of homologous protein sequences shows that these residues are more highly conserved than other residues in the loop. We conclude that β-breakers are the structural analogs of the N and C-terminal caps of α-helices. The identification of this aperiodic substructure suggests a strategy for improving secondary structure prediction and may guide site-directed mutagenesis experiments.