Hg(II) ion specifically binds with T:T mismatched base pair in duplex DNA.
Hg(II) ion specifically binds with T:T mismatched base pair in duplex DNA.
复制标题
DOI：
10.1002/chem.201001171
复制
发表时间：
2010-11
期刊：
影响因子：
--
通讯作者：
H. Torigoe;A. Ono;T. Kozasa
中科院分区：
文献类型：
--
作者：
H. Torigoe;A. Ono;T. Kozasa
金属离子介导的碱基对形成是寡核苷酸中人工碱基与金属离子相互作用的结果，在纳米技术中具有潜在的应用价值。我们最近发现T：T错配碱基对与Hg（II）离子结合在双链DNA中产生一种新的金属介导的碱基对。具有T-Hg-T碱基对的双链体的热稳定性与相应的T：A或A：T的热稳定性相当。由于不需要耗时的合成，涉及天然碱基胸腺嘧啶的新型T-Hg-T碱基对比涉及人工碱基的金属介导的碱基对更方便。在这里，我们研究的特异性和热力学性质的汞（II）离子和T：T错配碱基对之间的结合。只有熔化温度的双链体与T：T，而不是完全匹配或其他不匹配的碱基对被发现，特别是增加在汞（II）离子的存在下。Hg（II）与T：T错配碱基对的结合摩尔比为1：1，结合常数为10（6）M（-1），明显高于非特异性金属离子与DNA的结合常数。此外，高阶结构的双链体没有显着扭曲的Hg（II）离子结合。我们的研究结果支持的想法，T-Hg-T碱基对可能最终导致在纳米技术中的金属介导的碱基对的潜在应用的进展。
Metal-mediated base pair formation, resulting from the interaction between metal ions and artificial bases in oligonucleotides, has been developed for its potential application in nanotechnology. We have recently found that the T:T mismatched base pair binds with Hg(II) ions to generate a novel metal-mediated base pair in duplex DNA. The thermal stability of the duplex with the T-Hg-T base pair was comparable to that of the corresponding T:A or A:T. The novel T-Hg-T base pair involving the natural base thymine is more convenient than the metal-mediated base pairs involving artificial bases due to the lack of time-consuming synthesis. Here, we examine the specificity and thermodynamic properties of the binding between Hg(II) ions and the T:T mismatched base pair. Only the melting temperature of the duplex with T:T and not of the perfectly matched or other mismatched base pairs was found to specifically increase in the presence of Hg(II) ions. Hg(II) specifically bound with the T:T mismatched base pair at a molar ratio of 1:1 with a binding constant of 10(6) M(-1), which is significantly higher than that for nonspecific metal ion-DNA interactions. Furthermore, the higher-order structure of the duplex was not significantly distorted by the Hg(II) ion binding. Our results support the idea that the T-Hg-T base pair could eventually lead to progress in potential applications of metal-mediated base pairs in nanotechnology.