量化功能组相互作用,确定尿素对核酸螺旋形成的尿素作用
Emily J Guinn1, Jeffrey J Schwinefus, Hyo Keun Cha
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|March 21, 2013
概括
尿素破坏核酸和蛋白质的稳定. 这项研究量化了尿素的数量.
科学领域:
- 生物物理化学 生物物理化学
- 分子生物学分子生物学
- 化学热力学化学热力学
背景情况:
- 已知尿素会破坏蛋白质,核酸及其复合物的结构.
- 了解尿素与生物分子的相互作用对于探测形状变化至关重要.
- 之前的研究描述了尿素与蛋白质功能组的相互作用.
研究的目的:
- 量化尿素和核酸成分 (基,核酸,核酸) 之间的相互作用.
- 开发尿素作为核酸过程中结构变化的定量探针.
- 为了确定尿素与特定核酸功能群的相互作用潜力.
主要方法:
- 采用了度和六醇-水分布试验来测量化学潜在衍生物 (μ23).
- 通过剖析尿素-核酸成分相互作用的μ23值来获得相互作用潜力.
- 确定了DNA十二体双螺旋形成的尿素m值.
主要成果:
- 与水相比,尿素与核酸功能组 (芳香环,碳酸,酸盐,糖) 有有利的相互作用.
- 与异环芳环和甲基组的相互作用特别有利.
- 对于DNA双螺旋形成的尿素m值 (0.72-0.85 kcal mol(-1) m(-1)) 显示很少依赖GC含量.
结论:
- 为了解释观察到的尿素m值,需要在分离的DNA链中进行广泛的核基堆叠 (60-90%) .
- 结果在不同温度下的DNA和RNA十二相中以及与文献数据一致.
- 尿素作为一个有价值的定量探测器,用于核酸过程中可访问表面积 (ΔASA) 的变化.
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