不同离子分布对远程DNA电荷传输的影响
Tashica T Williams1, Jacqueline K Barton
1Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena, California 91125, USA.
Journal of the American Chemical Society
|February 28, 2002
概括
改变 DNA 的 DNA.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 电化学 电化学 电化学
背景情况:
- 对DNA修复和复制而言,DNA电荷传输至关重要.
- 了解影响DNA电荷传输的因素对于各种生物过程至关重要.
- 远程氧化损伤作为研究DNA电荷动态的宝贵探针.
研究的目的:
- 为了研究离子分布对DNA电荷传输的影响.
- 为了划分终端电荷放置对DNA孔运输的影响.
- 探索DNA序列和内部介电常数在电荷传输中的作用.
主要方法:
- 用光氧化剂连接的DNA组件的构建.
- 光氧化剂与容易受到氧化损伤的瓜宁部位的空间分离.
- 通过测量远距离/近距离氧化损伤比率来评估电荷传输.
- 损坏比率的比较,使用不同的终端32P标记来转移负电荷.
主要成果:
- 将负电荷移动到近接端显著减少了远距离孔运输.
- 这种效应在A6通道和混合DNA序列中都被观察到.
- 这些发现表明,由于终端电荷转移,瓜宁位点的热力学潜力的变化.
结论:
- 终端电荷分布影响长距离DNA电荷传输.
- 表明DNA基对的高内部介电常数.
- DNA的纵向极化性是电荷传输机制的一个关键因素.
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