聚氨酸在液体和双层膜之间通过阳离子介导的转移
1Department of Organic Chemistry, University of Geneva, Geneva, Switzerland. naomi.sakai@chiorg.unige.ch
Journal of the American Chemical Society
|November 20, 2003
概括
逆离子对富含guanidinium的oligo/聚合物产生关键影响,使膜转位成为可能. 特定的离子组合增强了聚氨酸的作用.
科学领域:
- 生物化学和生物物理学
- 膜生物学 膜生物学
- 聚合物科学 聚合物科学
背景情况:
- 富含guanidinium的oligo/聚合物在生物膜中表现出复杂的行为,包括转位和离子通道调节.
- 在调解这些相互作用方面,对抗的作用仍然不完全理解.
- 报告的现象包括HIV-Tat样转位和离子通道门.
研究的目的:
- 调查对抗离子对在膜环境中富含guanidinium的oligo/聚合物的行为的影响.
- 为了确定离子的身份和组合如何影响聚合物溶解性,相位转移和膜转位.
- 阐明关联丰富的奥利戈/聚合物功能的阳离子介导调节机制.
主要方法:
- 从水相转移到有机相 (chloroform) 的相转移实验,使用各种两性和水性离子.
- 通过使用聚氨酸载体,对5(6) - 碳氧化素 (CF) 复合体在散装甲膜上的转移进行研究.
- 在特定的双层和介质离子的存在下,通过聚氨酸调解的大型单层囊泡的CF外流的测定.
主要成果:
- 两性离子 (例如,SDS,EYPG,胆固醇硫酸盐) 促进了聚和六氨酸的相转移到.
- 水友性阴离子 (例如硫酸盐,ATP,肝素) 抑制了CF-多原氨酸复合物的转移到膜中.
- 二元和精制的离子尾酒 (例如,EYPG,酸盐,TFA) 是必要的,以激活聚氨酸作为有效的CF载体在散装和双层膜.
结论:
- 电荷和溶解度的阳离子介导变异性决定了富含guanidinium的/聚合物对不同环境的适应性.
- 特定的离子组合对于激活聚氨酸作为膜转位的载体至关重要.
- 阳离子相互作用的动态性质表明一种常见的,可适应的载体机制,有助于这些聚合物的复杂生物功能.
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