在Bilayers的形形状的NMR报告员
Siyuan Wang1,2, Flavio Della Sala1,2, Matthew J Cliff2
1Department of Chemistry, University of Manchester, Oxford Road, ManchesterM13 9PL, U.K.
Journal of the American Chemical Society
|November 15, 2022
概括
研究人员开发了一种新的-19 (F) 记者标签,用于跟踪细胞膜中的折形状. 这个标签证实了有机溶剂和脂双层之间的折叠体构成一致.
科学领域:
- 生物物理化学
- 分子生物学
- 材料科学
背景情况:
- 在脂双层中控制折形态对于它们作为分子信息继电器的应用至关重要.
- 开发有效的方法来监测膜环境中的这些构造是必不可少的.
研究的目的:
- 开发和使用一种新的F报告标签来表征折形状.
- 调查N端合控制器对折叠机螺旋性的影响.
- 为了比较有机溶剂与脂双层中的折叠剂构造偏好.
主要方法:
- 用 (R) -1- (三甲基) 乙胺 (R) -TFEA) 记者标签功能化的α-氨基酸 (Aib) 折叠体的合成.
- 用X射线结晶学来确定折叠体3的螺旋结构.
- 有机溶剂和小单层囊泡 (SUV) 悬浮液中的可变温度 (VT) 核磁共振 (NMR) 光谱.
- 19F 核磁共振光谱测定化学转移与折叠体构成的相关性.
主要成果:
- 晶体学证实了Aib折叠体的3个螺旋形状.
- 在溶液中与N端诱导的螺旋性 (M或P螺旋感) 相对应的 (R) -TFEA报告者的NMR化学转移.
- 脂双层中的NMR光谱显示了与有机溶剂相似的共振,表明了相似的形状偏好.
- 脂基性对折叠体形状的影响很小.
结论:
- (R) -TFEA报告标签有效地监测有机溶剂和脂双层中的折形状.
- 在这些不同的环境中保留了Foldamer的形状偏好.
- 这项研究为设计和控制膜模拟系统中的折叠器行为提供了有价值的工具.
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