CONFORMATION OF PROTEINS - HANDEDNESS OF "BETA-STRAND-ALPHA-HELIX-BETA-STRAND UNIT
CONFORMATION OF PROTEINS - HANDEDNESS OF "BETA-STRAND-ALPHA-HELIX-BETA-STRAND UNIT
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DOI：
10.1016/0022-2836(76)90099-1
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发表时间：
1976-01-01
影响因子：
5.6
通讯作者：
THORNTON, JM
中科院分区：
文献类型：
--
作者：
STERNBERG, MJE;THORNTON, JM
β-链-α-螺旋-β-链单元由2个平行但不一定相邻的β-位于β中的链，折叠片，并通过一个或多个α-螺旋这个单位，这发生在17个功能不同的球状蛋白质，可能会采取一个右或左手构象。分布分析显示，58个单位中有57个是右手使用者。如果单位没有右手偏好，观察到这种分布的概率是10-16。这可以用β的扭曲来解释。片，这是显示有利于右手单元，否则空间位阻发生在环区。右旋链-螺旋-链单元决定了在双链酶中发现的超二级结构和在其他结构中发现的相关折叠的意义。包含这个单位的蛋白质之间的进化关系重新评估这种偏好。该单位将以右手构象折叠的高概率对三级结构的预测具有影响。
The .beta.-strand-.alpha.-helix-.beta.-strand unit consists of 2 parallel, but not necessarily adjacent, .beta.-strands which lie in a .beta.-pleated sheet and are connected by one or more .alpha.-helices. This unit, which occurs in 17 functionally different globular proteins, may adopt a right- or a left-handed conformation. An analysis of the distribution shows that 57 out of the 58 units are right-handed. If the unit had no right-handed preference, the probability of observing such a distribution by chance is 10-16. This may be explained in terms of the twist of the .beta.-sheet which is shown to favor a right-handed unit, as otherwise steric hindrance occurs in the loop regions. The right-handed strand-helix-strand unit determines the sense of the super-secondary structure found in the dehydrogenases and of related folds found in other structures. The evolutionary relationships between proteins containing this unit are re-evaluated in terms of this preference. The high probability that the unit will fold with a right-handed conformation has implications for the prediction of tertiary structure.