Sequence dependence of cytochrome c electrochemistry on DNA modified electrodes: Effect of hydrogen bonding of a ligand to nucleobases opposite an abasic site
Sequence dependence of cytochrome c electrochemistry on DNA modified electrodes: Effect of hydrogen bonding of a ligand to nucleobases opposite an abasic site
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DOI：
10.1016/j.elecom.2008.01.008
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发表时间：
2008-03
影响因子：
5.4
通讯作者：
Yong Shao;Kotaro Morita;Qing Dai;S. Nishizawa;N. Teramae
中科院分区：
文献类型：
--
作者：
Yong Shao;Kotaro Morita;Qing Dai;S. Nishizawa;N. Teramae
用电化学方法研究了氢键形成配体与含碱性(AP)位点的DNA的结合，以识别与AP位点相反的核苷酸。以细胞色素c(Cyto C)为探针，用含AP位的DNA双链修饰金电极表面。Cyto c表现出准可逆的电化学行为，其行为依赖于与Ap中心相对的碱基。当AP位置对面的碱基是胞嘧啶时，观察到Cyto c电子转移的动力学要慢得多。这一观察结果可以用以前的报告解释，即碱基堆积被干扰的程度要大得多，因为AP位点对面的胞嘧啶碱基是以额外的螺旋翻转出来的。形成氢键的配体2-氨基-7-甲基-1，8-萘啶(AMND)与胞嘧啶的结合可以显著改善Cyto c的电化学行为，表明ANND结合导致了有效的碱基堆积。本方法展示了一种通过DNA介导的电荷转移来研究小配体与AP位点结合的简单方法。
The binding of a hydrogen bond-forming ligand to abasic (AP) site-containing DNA was electrochemically investigated for discrimination of a nucleotide opposite the AP site. The surface of a gold electrode was modified by AP site-containing DNA duplexes on which cytochrome c (Cyto c) was attached electrostatically as a probe. Cyto c showed quasi-reversible electrochemical behavior depending on the base opposite the AP site. When the base opposite the AP site was cytosine, much slower kinetics of Cyto c electron transfer was observed. This observation could be explained by previous reports that the base stacking was disturbed to a much greater extent because the cytosine base opposite the AP site was flipped out extra-helically. The binding of a hydrogen bond-forming ligand, 2-amino-7-methyl-1,8-naphthyridine (AMND), to cytosine opposite the AP site could significantly improve the electrochemical behavior of Cyto c, indicating effective base stacking due to the AMND binding. The present method demonstrates an easy way for investigating the binding of a small ligand to the AP site through DNA-mediated charge transfer.