Large electrostatic differences in the binding thermodynamics of a cationic peptide to oligomeric and polymeric DNA.
Large electrostatic differences in the binding thermodynamics of a cationic peptide to oligomeric and polymeric DNA.
复制标题
阳离子肽与寡聚和聚合 DNA 的结合热力学存在较大的静电差异。
DOI：
10.1073/pnas.93.6.2511
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发表时间：
1996
影响因子：
11.1
通讯作者：
RecordJr,MT
中科院分区：
文献类型：
--
作者：
Zhang,W;Bond,JP;Anderson,CF;Lohman,TM;RecordJr,MT
这里提出的结果表明，热力学的寡阳离子结合到聚合物和寡聚DNA是不等价的，因为长程静电效应。在生理阳离子浓度（0.1-0.3 M）下，寡聚赖氨酸八聚化KWK 6-NH 2（+8电荷）与单链聚（dT）的结合在每个位点上比相同配体与寡核苷酸dT（pdT）10（-10电荷）的结合强得多，并且显著更依赖于盐浓度。这些大的差异是一致的泊松-玻尔兹曼计算的模型，其特征在于与关键的预平均结构参数的电荷分布。因此，这里提出的实验和理论结果表明，聚合物核酸的疏水特性作出了很大的贡献，其与简单的寡阳离子配体的结合相互作用的幅度和盐浓度的依赖性。
Results presented here demonstrate that the thermodynamics of oligocation binding to polymeric and oligomeric DNA are not equivalent because of long-range electrostatic effects. At physiological cation concentrations (0.1-0.3 M) the binding of an oligolysine octacation KWK6-NH2 (+8 charge) to single-stranded poly(dT) is much stronger per site and significantly more salt concentration dependent than the binding of the same ligand to an oligonucleotide, dT(pdT)10 (-10 charge). These large differences are consistent with Poisson-Boltzmann calculations for a model that characterizes the charge distributions with key preaveraged structural parameters. Therefore, both the experimental and the theoretical results presented here show that the polyelectrolyte character of a polymeric nucleic acid makes a large contribution to both the magnitude and the salt concentration dependence of its binding interactions with simple oligocationic ligands.