基托多复合体:DNA在结合和释放时形成的能量和形状变化
Valerij Y Grinberg1, Tatiana V Burova2, Natalia V Grinberg2
1A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov St. 28, Moscow 119991, Russian Federation; N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin St. 4, Moscow 119991, Russian Federation.
International journal of biological macromolecules
|August 11, 2023
概括
基托多复合体以合作方式结合DNA,形成球状结构. 基托中的DNA构造和固定取决于基托/DNA比率和离子强度,影响多重复性行为.
科学领域:
- 生物物理化学 生物物理化学
- 聚合物科学 聚合物科学
- 分子生物学分子生物学
背景情况:
- 酸盐 (CS) 是一种生物相容的聚合物,在基因传递中具有潜在的应用.
- 了解酸盐和DNA之间的相互作用对于优化多重复的形成和稳定性至关重要.
- 结合酸盐后DNA的构造变化会影响其可访问性和功能.
研究的目的:
- 为了研究基托-DNA多重组形成的能量.
- 为了分析DNA结合在基因多复合体中的结构稳定性.
- 在不同的条件下,探索基托-DNA多重复的解离行为.
主要方法:
- 异热定位热量计 (ITC) 用于研究结合能量.
- 高灵敏度差分扫描热度计 (HS-DSC) 用于评估DNA结构稳定性.
- 基托/DNA重量比 (r_w) 和离子强度 (pH 5.0 和 7.4) 的变化.
主要成果:
- CS-DNA结合遵循一个合作机制 (麦吉-·希佩尔模型).
- 观察到两种DNA构造形式 (完好和球形),球形DNA在较高的CS含量中占主导地位.
- 多复合体在pH7.4时显示相分离,在CS丰富的相中固定DNA,在生理离子强度上有形状变化.
结论:
- 酸盐结合会诱导DNA凝结成稳定的球形形式.
- 多重复性稳定性和DNA构型可通过CS/DNA比率和离子强度进行调整.
- 基托多复合体显示出DNA固定和受控释放应用的潜力.
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