测量聚-脂质双层相互作用的静电学
Julianne M Troiano1, Alicia C McGeachy1, Laura L Olenick1
1Department of Chemistry, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|March 31, 2017
概括
像聚胺化物 (PAH) 这样的多基因与脂质双层相互作用而不会被破坏. 尽管吸附能量较低,但PAH通过凝结对离子覆盖膜表面,与其单体胺不同.
科学领域:
- 生物物理
- 材料科学
- 表面化学
背景情况:
- 了解多聚-膜相互作用对于控制它们的行为至关重要.
- 很难获得分子层面的多吸附和膜破坏的洞察力.
- 在生物医学应用中广泛使用多聚,需要了解它们的膜相互作用.
研究的目的:
- 阐明与脂质双层相互作用的分子机制.
- 量化聚胺化物 (PAH) 和胺化物 (AH) 的吸附行为和膜破坏潜力.
- 提供实验数据,以完善多离子-膜相互作用的理论模型.
主要方法:
- 使用第二和振动总频谱.
- 采用带有散射监控的石英晶体微平衡器 (QCM-D).
- 进行了广泛的计算机模拟以模拟多化物-膜相互作用.
主要成果:
- 在实验条件下,发现PAH对脂质二层的吸附是可逆的且无破坏性的.
- 与AH (-14.6 ± 0.4 kJ/mol) 相比,PAH具有较低的自由吸附能量 (-52.7 ± 0.6 kJ/mol).
- PAH利用凝结的对电离子来克服脊柱排斥,并在双层表面广泛吸附,其中氨基团显示了改变的pKa值.
结论:
- 对脂质膜的多离子吸附是一个复杂的过程,受反离子凝结和环境因素的影响.
- 与潜在的假设相反,PAH吸附不具有破坏性,并且涉及显著的结构重组.
- 这项研究为原子模拟提供了关键的实验约束,增强了聚化-膜相互作用的预测模型.
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