Dickerson R E, Drew H R
Proc Natl Acad Sci U S A. 1981 Dec;78(12):7318-22. doi: 10.1073/pnas.78.12.7318.
X-ray structure analysis of B-DNA double helix with sequence C-G-C-G-A-A-T-T-C-G-C-G has revealed several sequence-dependent structural features. Four of these are shown in this paper to be related to one another by simple structural or kinematic principles: (i) the correlation between glycosyl torsion and chi and main chain C4'--C3' torsion angle delta, (ii) the observations that purines prefer larger phi and delta angles than do pyrimidines, (iii) the anticorrelation of phi or of delta angles between sugars associated with one base pair, and (iv) the observation that successive base planes in purine-pyrimidine steps open up the angle between them toward the major groove, whereas pyrimidine-purine steps open toward the minor groove. These features offer the beginning of an understanding of the way in which specific base sequences can perturb the structure of a B-DNA double helix so as to be "read" by intercalating drugs, repressors, and other recognition proteins.
对序列为C-G-C-G-A-A-T-T-C-G-C-G的B-DNA双螺旋进行的X射线结构分析揭示了几个与序列相关的结构特征。本文表明其中四个特征通过简单的结构或运动学原理相互关联：（i）糖基扭转角与χ角以及主链C4'-C3'扭转角δ之间的相关性；（ii）嘌呤比嘧啶更喜欢更大的φ角和δ角的观察结果；（iii）与一个碱基对相关的糖之间的φ角或δ角的反相关性；（iv）嘌呤-嘧啶步中连续碱基平面之间的角度朝着大沟打开，而嘧啶-嘌呤步朝着小沟打开的观察结果。这些特征为理解特定碱基序列如何扰动B-DNA双螺旋结构从而被嵌入药物、阻遏物和其他识别蛋白“读取”提供了开端。
