Haworth I S, Rodger A, Richards W G
Physical Chemistry Laboratory, Oxford, U.K.
Proc Biol Sci. 1991 May 22;244(1310):107-16. doi: 10.1098/rspb.1991.0058.
Molecular mechanics calculations of the binding of spermine to a number of solvated DNA helices have led to the development of a new model for spermine complexation. The structural details of the complexes formed with d(GCGCGCGCGC)2 and d(ATATATATAT)2 decamers allowed a rationalization of the observed experimental differences for binding to these two helices. For d(ATATATATAT)2 it was concluded that spermine remains in a cross-major groove binding site. Conversely, for d(GCGCGCGCGC)2 spermine reorientation via specific ligand-base-pair hydrogen-bond formation allows complexation along the major groove. The solvent plays an important role in differentiating the two binding modes. A mechanism of spermine complexation to natural DNA is postulated from these results. Past experimental data are also considered in the context of the new model.
对精胺与多个溶剂化DNA螺旋结合的分子力学计算，促成了一种新的精胺络合模型的建立。与d(GCGCGCGCGC)2和d(ATATATATAT)2十聚体形成的复合物的结构细节，使得我们能够合理解释观察到的这两种螺旋结合的实验差异。对于d(ATATATATAT)2，得出的结论是精胺保留在一个跨大沟结合位点。相反，对于d(GCGCGCGCGC)2，精胺通过特定的配体-碱基对氢键形成重新定向，从而允许沿着大沟进行络合。溶剂在区分这两种结合模式中起着重要作用。基于这些结果推测了精胺与天然DNA络合的机制。过去的实验数据也在新模型的背景下进行了考量。
