由结合性非理想性诱导的含有宏分子拥挤剂的巨型囊泡的脉动性
Wan-Chih Su, Douglas L Gettel, Morgan Chabanon1
1Department of Mechanical and Aerospace Engineering, University of California San Diego , La Jolla, California 92093, United States.
Journal of the American Chemical Society
|January 6, 2018
概括
具有宏分子拥挤剂的巨型脂质囊泡经历了透压力差异,导致水流入和周期性膨胀爆发事件. 这些事件会排出挤压剂,降低透压力并稳定囊泡.
科学领域:
- 聚合物物理
- 生物物理
- 物理化学
背景情况:
- 溶液中的大分子在聚合性特性中表现出非微不足道的偏差.
- 巨型脂质囊是细胞膜和透反应的模型系统.
研究的目的:
- 调查含有宏分子拥挤剂的巨型脂质囊泡在暴露于小分子氧化物时的透行为.
- 阐明在透应激下水运输和膜动力学的机制.
主要方法:
- 在受控的透条件下对巨型脂质囊泡的实验观察.
- 理论连续模型的开发和应用,包括粘度,扩散性和协同非理想性.
- 计算机模拟分析膨胀爆发周期和孔隙动态.
主要成果:
- 大分子的结合性非理想性诱导了穿过囊泡膜的透压差.
- 水的流入导致周期性的膨胀爆发事件,其特点是尺寸,张力和相位分离的振荡.
- 过时的孔隙形成介导着宏分子的逐步排放,减少了透差异.
- 理论模型和模拟准确地复制实验观测,包括循环细节和孔隙寿命.
结论:
- 巨大的囊泡中的宏分子拥挤会影响它们对透冲击的反应,模仿红细胞的行为.
- 透应力反对囊泡内自发的大分子过度拥挤.
- 除了奥斯莫斯压力效应之外,显著的过度拥挤需要特定的相互作用.
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