[2'-脱氧核糖多核苷酸糖磷酸骨架的最简单分子模型：量子化学充分性检验]

[The simplest molecular model of 2'-deoxyribopolinucleotides sugar-phosphate backbone: quantum-chemical adequacy check].

作者信息

Voĭteshenko I S, Zhurakivs'kyĭ R O, Bulavin L A, Govorun D M

出版信息

Ukr Biokhim Zh (1999). 2011 May-Jun;83(3):106-12.

Abstract

The physical adequacy of the simplest molecular model "sugar residue (SR)--phosphate group (PG)--SR" of 2'-deoxyribopolinucleotides sugar-phosphate backbone is confirmed at DFT B3LYP/6-31++G(d,p) and DFT B3LYP/6-31G(d,p) of quantum-chemical methods. It is proved that complicacy of the model to the "SR-PG-SR-PG-SR" and higher levels does not noticeably change the numerical values of torsion angles. Also these angles depend negligibly on counterion nature (e.g. Na+ to Li+, K+ or Cs+ change) and transition from vacuum to continuum approximation with medium dielectrical values of 1.4, 24.9, and 78.4. It is shown that model loses its adequacy when PG is the end link.

摘要

通过量子化学方法中的密度泛函理论（DFT）B3LYP/6 - 31++G(d,p) 和 DFT B3LYP/6 - 31G(d,p)，证实了2'-脱氧核糖多核苷酸糖 - 磷酸骨架最简单分子模型“糖残基（SR） - 磷酸基团（PG） - SR”在物理上的合理性。结果表明，将模型扩展到“SR - PG - SR - PG - SR”及更高层次的复杂性，并不会显著改变扭转角的数值。而且这些角度对抗衡离子的性质（例如从Na⁺变为Li⁺、K⁺或Cs⁺）以及从真空到介电常数分别为1.4、24.9和78.4的连续介质近似的转变几乎没有依赖性。研究表明，当PG作为末端连接时，该模型失去了其合理性。