紫外线下电流分辨率X射线结构细节水-水相互作用
Urszula Kosinska Eriksson1, Gerhard Fischer1, Rosmarie Friemann1
1Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, S-40530 Göteborg, Sweden.
Science (New York, N.Y.)
|June 15, 2013
概括
这项研究揭示了酵母水素的高分辨率结构,详细说明了它们的关键动机如何促进水的运输,同时阻断了通过特定水的配置和运动的质子流.
科学领域:
- 结构生物学 结构生物学
- 生物物理学的生物物理.
- 膜生物学 膜生物学
背景情况:
- 水相蛋白是不可分割的膜蛋白,对于细胞膜中水的运输至关重要.
- 它们的功能依赖于保存的动机:阿斯巴拉金--氨酸 (NPA) 签名和芳香/氨酸选择性过器 (SF).
研究的目的:
- 为了阐明水素素功能的高分辨率结构基础.
- 为了可视化道内的水分子相互作用,并了解选择性机制.
主要方法:
- 在0.88安格斯特罗姆分辨率的X射线晶体学.
- 分析结相互作用和残留物 tautomeric 状态.
- 水分子动力学和质子运输路径的计算建模.
主要成果:
- 详细可视化阿斯巴拉金-氨酸-氨酸 (NPA) 基因与水的相互作用.
- 在选择性过器 (SF) 中观察极化水的配置.
- 识别SF中距离较近的水位,通过Grotthuss机制防止同时占用和质子传输.
结论:
- 这种高分辨率的结构解释了aquaporin的水选择性和质子阻塞.
- 在SF内的相关运动破坏了水链连接,抑制了质子导电.
- 这为了解水素中介运输提供了分子基础.
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