与双吡啶盐相互作用时DNA手性光学性质的序列依赖性变化。

Sequence-dependent changes in the chiroptical properties of DNA upon interaction with dipyrandium.

作者信息

Vorlícková M, Kypr J, Kleinwächter V

出版信息

Biochim Biophys Acta. 1985 Feb 15;838(2):236-43. doi: 10.1016/0304-4165(85)90084-4.

Abstract

Interaction of dipyrandium with DNA and its dependence on the base sequence was studied using circular dichroism. It was found that calf thymus DNA and polynucleotide duplexes with alternating purine-pyrimidine sequences containing GC basepairs underwent similar alterations in the chiroptical properties upon binding of dipyrandium. The alterations suggest that these DNAs have similar B-type structures which may kink at the dipyrandium binding sites. On the other hand, poly(dA-dT).poly(dA-dT) and especially poly(dA-dU).poly(dA-dU) exhibit some features of A-type structure. Poly(dA-dT).poly(dA-dT) changes its chiroptical properties little when complexed with dipyrandium, as if it contained some type of kinks as equilibrium structural elements.

摘要

利用圆二色性研究了双吡啶盐与DNA的相互作用及其对碱基序列的依赖性。发现小牛胸腺DNA以及含有GC碱基对的嘌呤-嘧啶交替序列的多核苷酸双链体在结合双吡啶盐后，其旋光性质发生了类似的变化。这些变化表明这些DNA具有相似的B型结构，在双吡啶盐结合位点可能会发生扭结。另一方面，聚（dA-dT）·聚（dA-dT），尤其是聚（dA-dU）·聚（dA-dU）呈现出一些A型结构的特征。聚（dA-dT）·聚（dA-dT）与双吡啶盐复合时，其旋光性质变化很小，就好像它含有某种作为平衡结构元件的扭结。