在DNA中洞转移动学的HOMO能量差距依赖性
Kiyohiko Kawai1, Mitsuo Hayashi, Tetsuro Majima
1The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan.
Journal of the American Chemical Society
|February 17, 2012
概括
改变DNA基之间的能量差距显著影响了电荷转移速率. 减少这种差距可以提高孔的传输速度,从而能够精确控制DNA电荷传输.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 有机化学 有机化学
背景情况:
- DNA包括关氨酸-细胞氨酸 (G-C) 和腺氨酸-氨酸 (A-T) 基对.
- 占用率最高的分子轨道 (HOMO) 位于 purin 基 (G 和 A) 上.
- 穿过连续Gs或As的孔转移超过10^9s^-1,但在混合序列中减慢.
研究的目的:
- 研究HOMO能量差距 (Δ(HOMO)) 对DNA孔转移动学的影响.
- 探索如何变化 Δ(HOMO) 影响DNA中的电荷传输效率.
主要方法:
- 使用自然和人工核基,具有不同的HOMO水平.
- 系统地改变了相邻DNA基之间的HOMO能量差距.
- 在经过修改的DNA序列中测量和分析了孔转移率.
主要成果:
- 在DNA中,通过降低 Δ(HOMO) 的方法,可以显然增加孔转移率.
- 孔传输速率可以通过调整 Δ(HOMO) 来微调三个数量级.
- 在Δ(HOMO) 和电荷传输动力学之间存在明显的相关性.
结论:
- 人类能量差距是DNA中电荷传输效率的关键决定因素.
- 调节 Δ ((HOMO) 为控制 DNA 电荷传递速率提供了一种可行的策略.
- 这些发现对基于DNA的电子和分子通信有影响.
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