光驱动的五秒到百万秒的结构变化
Petr Skopintsev1, David Ehrenberg2, Tobias Weinert1
1Laboratory of Biomolecular Research, Biology and Chemistry Division, Paul Scherrer Institut, Villigen, Switzerland.
Nature
|June 6, 2020
概括
研究人员使用序列结晶学可视化了Krokinobacter eikastus rhodopsin 2 (KR2) 的光循环. 这揭示了结构变化如何使光驱动的通过膜传输.
科学领域:
- 生物物理
- 结构生物学
- 视觉遗传学
背景情况:
- 光驱动的,如克罗基诺巴克特 eikastus rhodopsin 2 (KR2),对于微生物的能量转化和有价值的光遗传工具至关重要.
- 之前的研究解决了KR2的静态结构,但使活性运输成为可能的动态结构变化仍然不清楚.
研究的目的:
- 阐明KR2在光循环期间的时间解析结构动态.
- 了解光驱动的细胞膜转移的分子机制.
主要方法:
- 在瑞士X射线自由电子激光器进行串行X射线晶体学.
- 时间分辨率数据收集在探头延迟的范围 (femtosecond到毫秒).
- 结构数据与光谱方法和量子化学计算的整合.
主要成果:
- 高分辨率的快照捕捉到KR2的结构变化,
- 视网膜异质化和结合口袋重组发生在纳米秒内.
- 一个静电门在微秒内打开,随后在视网膜附近发生过渡性结合.
- 在20毫秒后,在细胞外出口附近发现了第二个潜在的结位.
结论:
- 这项研究提供了前所未有的分子洞察力,
- 确定了KR2功能的关键结构介质和时间.
- 进步了对活性阳离子传输机制和光遗传工具操作的理解.
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