通过DNA领域的电荷传输的序列依赖性
Fangwei Shao1, Katherine Augustyn, Jacqueline K Barton
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|December 8, 2005
概括
DNA氧化对序列和结构都很敏感. 研究人员研究了DNA复杂体中N4-cyclopropylcytosine (CPC) 和N2-cyclopropylamine-guanosine (CPG) 的光氧化,发现序列显著影响电子孔传输.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 物理化学 物理化学
背景情况:
- 电子孔陷对于理解DNA电荷传输至关重要.
- N4-cyclopropylcytosine (CPC) 和N2-cyclopropylamine-guanosine (CPG) 是快速的电子孔陷,被纳入DNA复合体中.
- 光氧化研究利用各种光氧化剂,包括和复合物,以及绑定的.
研究的目的:
- 为了研究CPC和CPG在不同序列的DNA复合体中的光氧化.
- 确定DNA序列和结构对电子孔定位和传输的影响.
- 开发一种用于DNA中电荷传输的机械模型.
主要方法:
- 将CPC和CPG纳入具有不同序列的DNA复合体.
- 使用非共结合的和复合体,以及结合的.
- 基础分解的分析作为测量孔位的测量.
- 通过单基和双基替换调节DNA序列.
主要成果:
- 在光氧化后,CPC和CPG呈现差异性分解,表明孔位的位置不同.
- CPC光氧化受[Rh(phi) 2(bpy) ]3+的影响,而CPG则与[Rh(phi) 2(bpy) ]3+和[Ru(dppz) ((bpy') ]3+反应.
- 不仅仅是干预基,DNA序列也控制着CPC氧化,观察到至少三个基的域大小.
结论:
- DNA电荷传输对DNA序列和结构非常敏感.
- 通过短暂的,非局部化的DNA域进行构造性封闭的电荷传输模型解释了观察到的现象.
- 这种依赖序列和结构的电荷传输机制不同于极子模型.
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