Plesiewicz E, Stepień E, Bolewska K, Wierzchowski K L
Nucleic Acids Res. 1976 May;3(5):1295-306. doi: 10.1093/nar/3.5.1295.
Stacking self-association equilibria in aqueous solutions of m3uridine, m34,2',3',5'uridine, 2'-deoxyuridine, m13,4,4cytosine, m14,4,4,5cytosine, s2cytidine and s4thymidine were studied at various temperatures by vapour-pressure osmometry. Equilibrium constants Kst's were computed on the assumption of the isodesmic model of self-association. Enthalpies of association were also obtained from the temperature dependence of Kst according to the van't Hoff equation. Analysis of the equilibrium and thermodynamic parameters demonstrated involvement of hydrophobic interactions in the stabilization of complexes of tetramethyluridine. Dipole-induced dipole interactions seem to predominate in the formation of s2C, s4T and of both dimethylaminocytosine complexes.
通过蒸气压渗透法在不同温度下研究了3'-甲基尿苷、3',4,2',3',5'-尿苷、2'-脱氧尿苷、1'-甲基-3,4,4'-胞嘧啶、1'-甲基-4,4,4',5'-胞嘧啶、2'-硫代胞苷和4'-硫代胸苷在水溶液中的堆积自缔合平衡。根据自缔合的等键模型计算平衡常数Kst。根据范特霍夫方程,还从Kst对温度的依赖性中获得了缔合焓。对平衡和热力学参数的分析表明,疏水相互作用参与了四甲基尿苷复合物的稳定。在2'-硫代胞苷、4'-硫代胸苷以及两种二甲基氨基胞嘧啶复合物的形成中,偶极-诱导偶极相互作用似乎占主导。