Nonplanar DNA base pairs.
Nonplanar DNA base pairs.
复制标题
非平面 DNA 碱基对。
DOI：
10.1080/07391102.1996.10508895
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发表时间：
1996
影响因子：
4.4
通讯作者：
Jerzy Leszczynski
中科院分区：
文献类型：
--
作者：
J. Šponer;Jan Florián;Pavel Hobza;Jerzy Leszczynski
用可靠的从头算量子力学方法研究了30多个氢键核酸对的三维结构。我们发现，许多氢键键合的核酸碱基对本质上是非平面的，主要是由于其氨基的氮原子的部分sp3杂化和次级静电相互作用。这一发现扩展了DNA碱基的分子间相互作用的可变性，因为i）碱基对的柔性大于之前假设的，和ii）允许在碱基对平面之外定向的吸引质子-质子受体相互作用。例如，所有四个G-A错配碱基对都是螺旋桨扭曲的，并且非平面结构的能量偏好范围从小于0.1 kcal/mol到1.8 kcal/mol。我们预测，非平面性的氨基鸟嘌呤在G（反）…d（CCAAGATTGG）2晶体结构的ApG台阶的（反）对是将该结构的能量提高几乎3 kcal/mol的重要稳定因素。目前使用的经验势不够准确，不能正确地涵盖与氨基和碱基对非平面性相关的相互作用。
Three-dimensional structures of a representative set of more than 30 hydrogen-bonded nucleic acids pairs have been studied by reliable ab initio quantum mechanical methods. We show that many hydrogen-bonded nucleic acid base pairs are intrinsically nonplanar, mainly due to the partial sp3 hybridization of nitrogen atoms of their amino groups and secondary electrostatic interactions. This finding extends the variability of intermolecular interactions of DNA bases in that i) flexibility of the base pairs is larger than has been assumed before, and ii) attractive proton-proton acceptor interactions oriented out of the base pair plane are allowed. For example, all four G-A mismatch base pairs are propeller twisted, and the energy preferences for the nonplanar structures range from less than 0.1 kcal/mol to 1.8 kcal/mol. We predict that nonplanarity of the amino group of guanine in the G(anti)...A(anti) pair of the ApG step of the d(CCAAGATTGG)2 crystal structure is an important stabilizing factor that improves the energy of this structure by almost 3 kcal/mol. Currently used empirical potentials are not accurate enough to properly cover the interactions associated with amino-group and base-pair nonplanarity.
影响因子：
5.6
作者：
CHOU, SH;CHENG, JW;REID, BR
通讯作者：
REID, BR
DOI：
10.1073/pnas.88.1.26
发表时间：
1991-01-01
影响因子：
11.1
作者：
LI, Y;ZON, G;WILSON, WD
通讯作者：
WILSON, WD