在嵌入在B型DNA中的关氨-细胞因子基离子中进行质子转移
Hsing-Yin Chen1, Chai-Lin Kao, Sodio C N Hsu
1Department of Medicinal and Applied Chemistry and Center of Excellence for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan. hychen@kmu.edu.tw
Journal of the American Chemical Society
|October 29, 2009
概括
电子的附着触发了瓜-氨酸 (G:C) 基对中的质子转移,这对DNA电荷传输和损伤至关重要. G:C堆叠和水合有很大影响这个过程,影响DNA稳定性和修复机制.
科学领域:
- * 分子生物物理学 * 分子生物物理学
- * 计算化学 计算机化学
- * DNA 损伤机制
背景情况:
- * 关氨酸-氨酸 (G:C) 基对中的质子转移对于DNA电荷传输和辐射损伤至关重要.
- *以前的研究集中在孤立的基上,使得DNA复合体内的行为不清楚.
- * 了解影响G:C质子转移的环境因素对于DNA完整性至关重要.
研究的目的:
- * 通过量子力学计算,研究减少的G:C堆中的质子转移反应.
- *阐明环境因素对G:C(*-) 质子转移在DNA环境中的影响.
- *确定基堆叠,水化,骨干和离子在G:C质子转移能量中的作用.
主要方法:
- * 量子力学计算被用来模拟G:C堆中的质子转移.
- *分析重点是能源,包括反应障碍和能量变化.
- * 调查了G:C堆叠,水化,糖酸盐骨干和反的影响.
主要成果:
- *G:C堆中的质子转移是内热的,与孤立的G:C相比,它的屏障更高.
- *来自G:C堆叠的静电相互作用,而不是电荷移位,驱动了这种效应.
- *水化显著促进质子转移;堆叠和水化是关键因素,而骨干和离子起到较小的作用.
- * 嵌入的G:C对可以在散装水合中稳定两个多余的电子,形成可导致DNA损伤的二离子.
结论:
- * G:C堆积和水合极大地改变了质子转移的能量,影响了DNA的电荷传输和损伤.
- *水合水平是电荷传输和低能电子诱导的DNA损伤的关键决定因素.
- * 在水合的G:C对中形成稳定的二离子表明了诱导DNA损伤的机制.
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