在Xanthorhodopsin Kin4B8B8中进行质子增强的能量转移
Kazuhiro J Fujimoto1,2, Yuta A Tsuzuki2, Masae Konno3
1Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan.
The journal of physical chemistry letters
|November 6, 2025
概括
这项研究揭示了淡水桑托罗多普辛 (XR) 如何通过提高光采集效率来适应酸性条件. 特定氨基酸的质子化促进了胡卜素和视网膜之间的能量转移,在不断变化的水生环境中优化了光捕获.
科学领域:
- 生物化学 生物化学
- 频谱学是一种光谱学.
- 量子化学 是一个量子化学.
背景情况:
- 微生物罗多普辛对于水生生态系统中的光采集至关重要.
- 桑多多普辛 (XRs) 独特地利用视网膜和胡卜素来捕捉光.
- 了解XR适应环境pH值对于水生生化学至关重要.
研究的目的:
- 研究一种新鲜的淡水XR,Kin4B8.8中的pH依赖的能量转移效率.
- 在酸性条件下阐明改变了白蛋白到视网膜激发能量转移 (EET) 背后的分子机制.
- 确定特定氨基酸质子化状态在调节XR功能的作用.
主要方法:
- 用光谱测量来分析光吸收和能量转移.
- 量子化学计算以建模电子合和光谱重叠.
- 对XR行为的pH依赖性分析,重点关注关键残留物His60和Asp94.4.
主要成果:
- 在酸性pH下,Kin4B8的白蛋白-视网膜EET效率从40%增加到55%.
- Asp94的质子化显著增强了白蛋白-视网膜电子合.
- 尽管光谱红移,增强的合补偿减少重叠,增加EET率1.07倍.
结论:
- Asp94的质子化是Xanthorhodopsins中EET的pH响应调整的一个关键机制.
- 罗多普辛-胡卜素复合体通过pH-依赖的能量转移调制适应不同的光环境.
- 这项研究提供了对各种水生息地的光采集蛋白的适应策略的见解.
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