连接perylenediimide的DNA发针的疏水二元化和热解离
Mahesh Hariharan1, Yan Zheng, Hai Long
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|April 23, 2009
概括
二胺 (PDI) 染色体结合的寡核酸针在盐中形成二次体,影响其结构和光谱性质. 这些发现促进了对DNA纳米结构及其相互作用的理解.
科学领域:
- 超分子化学 超分子化学
- 生物物理化学 生物物理化学
- 橄核酸的化学成分
背景情况:
- 与染色体结合的寡核酸合物是纳米技术的关键.
- 二胺 (PDI) 是用于此类应用的多功能染色体.
- 了解这些结合物的自我组装和特性至关重要.
研究的目的:
- 为了研究发针形成的bis ((oligonucleotide) 与PDI链接器结合的结构和特性.
- 阐明盐度在它们组合中的作用 (单质与二质).
- 描述不同形状状态的光谱行为.
主要方法:
- 光谱技术 (UV-Vis,CD) 是一种
- 计算方法 (分子动力学,平均力的潜力)
- 微角X射线散射 (SAXS) 是一种微角X射线散射技术.
主要成果:
- 结合物存在于没有盐的单体发针形式,以及具有>50mM NaCl.的头对头二极体形式.
- 盐的依赖与阴离子凝结有关.
- 加热诱导从二聚体到单聚体到随机线圈的连续解离,盐-依赖.
- 对单体和二元状态观察到不同的光谱性质.
- 证据表明PDI和DNA基之间的电子相互作用.
- 低光量子产量和皮秒时间尺度结构放松在二次体中.
结论:
- 与PDI结合的寡核酸针表现出依赖盐的自我组装成单体和二元体.
- 这些结构变化极大地影响了它们的光谱性质.
- 该研究提供了对DNA结构,染色体相互作用和溶液条件之间的相互作用的见解.
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