Department of Chemistry, Wesleyan University, Middletown, Connecticut 06459, United States.
J Am Chem Soc. 2011 Mar 23;133(11):3687-9. doi: 10.1021/ja102601h. Epub 2011 Mar 1.
The effects of modifying the electronic characteristics of nonpolar base analogues substituted at positions involved in stacking interactions between SL2 RNA and the U1A protein are described. A surprisingly large difference in the stability between complexes formed with base analogues that differ only in the position of substitution of a single fluorine atom is observed. The results of high-level ab initio calculations of the interactions between the nonpolar base analogue and the amino acid side chain correlate with the experimentally observed trends in complex stability, which suggests that changes in stacking interactions that result from varying the position and degree of fluorine substitution contribute to the effects of fluorine substitution on the stability of the U1A-SL2 RNA complex.
描述了改变非极性碱基类似物电子特性的影响，这些类似物在 SL2 RNA 和 U1A 蛋白之间的堆积相互作用涉及的位置上被取代。令人惊讶的是，仅在取代单个氟原子的位置上有所不同的碱基类似物形成的复合物之间的稳定性存在很大差异。非极性碱基类似物与氨基酸侧链之间相互作用的高级从头算计算结果与实验观察到的复合物稳定性趋势相关，这表明由于取代位置和氟取代程度的变化而导致的堆积相互作用的变化有助于氟取代对 U1A-SL2 RNA 复合物稳定性的影响。
