在PixD光感受器中的不同符合器之间,电荷分离能量的差异
Tomoyasu Noji1,2, Hiroyuki Tamura1,2, Hiroshi Ishikita1,2
1Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan.
The journal of physical chemistry. B
|November 28, 2023
概括
蓝光使用黄素 (BLUF) 域蛋白作为光受体. 这是一个 PixD BLUF 域名.
科学领域:
- 生物化学 生物化学
- 摄影化学的使用.
- 分子生物学分子生物学
背景情况:
- 蓝光使用黄素 (BLUF) 域蛋白质是各种各样的生物体的关键光受体.
- 皮克斯D BLUF域表现出两种不同的构造:W91out和W91in,不同的是基91 (Trp91) 与黄单核酸 (FMN) 染色体的接近程度.
研究的目的:
- 为了研究两个PixD BLUF域构造中的电荷分离和二基态的能量.
- 为了阐明在BLUF蛋白中控制信号传导的结构动力学.
主要方法:
- 采用量子力学/分子力学/极化连续模型 (QM/MM/PCM) 方法.
- 分析了光激发,电荷分离和激进状态的稳定性和能量景观.
主要成果:
- 在W91out形状中,电荷分离状态 (FMN•-) 比光激发状态 (FMN*) 更稳定.
- 在W91形状中,来自Ser28的静电排斥使FMN不稳定,阻碍了电荷分离.
- W91out形状通过电荷重组促进了基态 (FMNH•) 和随后的信号状态的形成,而W91in则导致回归到适应黑暗的状态.
结论:
- 在PixD BLUF蛋白中,W91out形状对于启动信号级联是必不可少的.
- 形态动力学,特别是W91位置,决定了BLUF光感受器中光激活的功能结果.
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