在没有溶剂的环境中,在多d(CG) n寡核酸中形成双重体和出现螺旋性
Jennifer Gidden1, Alessandra Ferzoco, Erin Shammel Baker
1Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|November 19, 2004
概括
气相离子移动性实验显示,较长的细胞因子/瓜DNA复合体 (10-mer和更大) 保留了它们的溶液结构,采用了螺旋形状. 较短的双重体更喜欢气相中的球形形状.
科学领域:
- 生物物理化学 生物物理化学
- 结构生物学 结构生物学
- 计算化学计算化学
背景情况:
- 了解DNA双重结构对于分子生物学至关重要.
- DNA的气相构造可能与溶液结构有很大差异.
- 离子流动性与分子动力学相结合,为分子形状和稳定性提供了洞察力.
研究的目的:
- 为了研究不同长度的细胞因子/瓜氨酸DNA复合体的气相构造.
- 将实验性离子运动数据与理论分子动力学模拟进行比较.
- 为了确定DNA复合体是否在气相中保留类似溶液的结构.
主要方法:
- 电子喷射电离,以产生去质子化DNA双重离子.
- 离子运动谱测量用于测量中的碰撞横截面.
- 分子动力学模拟以建模理论构造和稳定性.
主要成果:
- 4-mer和6-mer双体采用了球形形状.
- 8-mer双重体显示了球形和螺旋形,球形是最受欢迎的.
- 10-mer,14-mer和18-mer双人机主要呈现螺旋结构.
- 观察到螺旋结构,预计在气相中不稳定,表明溶液结构的保留.
结论:
- 基因复合体可以在毫秒时间尺度上在气相中保持类似溶液的螺旋形状.
- 双重DNA的长度会影响其气相结构偏好.
- 离子流动性是一种强大的工具,可以在没有溶剂的情况下探测生物分子的结构动力学.
相关概念视频
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