跨膜孔的计算设计
Chunfu Xu1,2,3, Peilong Lu4,5,6,7, Tamer M Gamal El-Din8
1Institute for Protein Design, University of Washington, Seattle, WA, USA.
Nature
|August 28, 2020
概括
科学家使用同心的α螺旋环计算设计了稳定的蛋白质孔. 这些设计的跨膜孔有选择地导出离子,并允许分子通过,从而促进生物技术应用.
科学领域:
- 生物物理
- 结构生物学
- 生物技术
背景情况:
- 跨膜通道和毛孔对于生物过程和DNA纳米孔测序等应用至关重要.
- 为选择性离子导电或分子通道设计稳定,明确的跨膜蛋白孔是一个重大挑战.
- 之前的工作包括合成形成通道和de novo膜蛋白设计的进步.
研究的目的:
- 通过计算设计由同心的α螺旋环形成的稳定,单分散的蛋白质孔.
- 在水溶性和跨膜形式上对这些设计的毛孔进行结构和功能特征.
- 展示这些设计孔在离子选择性和分子运输中的应用潜力.
主要方法:
- 一致的α螺旋环结构的计算蛋白质设计.
- 用X射线结晶学来确定水溶性孔隙的结构.
- 补丁电生理学评估细胞膜中的离子运输.
- 在体外蛋白质合成和脂质体结合用于分子通道研究.
- 用冷电子显微镜可视化膜外孔结构.
主要成果:
- 设计的12和16螺旋孔的晶体结构与计算模型非常相匹配.
- 在昆虫细胞中,跨膜12螺旋孔显示选择性过.
- 跨膜16螺旋孔促进了小分子光体 (生物化Alexa Fluor 488) 在脂质体中的通道.
- 低温电子显微镜证实了16螺旋转膜孔的结构.
结论:
- 这项研究成功设计和验证了稳定,明确的跨膜蛋白孔.
- 这些设计孔具有选择性的离子导电和分子运输能力.
- 这些发现为创建各种生物技术应用的定制蛋白道和毛孔开辟了道路.
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