光受体蛋白的光物理和光化学特性的理论研究

Light plays a crucial role in all kingdoms of life and functions. Light-induced signal transduction is a very important and interesting research field. Research studies on photoactive yellow protein and phytochrome are very active. However, relatively few theoretical studies have been performed so far, and many issues and questions are still unsolved, especially at the atomic, molecular and long-time resolution. To deeply understand and study photophysics and photochemistry of the photoreceptor proteins, more efficient simulation methods will be performed and developed to focus on quantum refinement of high-energy electronic ground-state and excited-state structures, mechanisms of photo-isomerization and photo-induced interconversion of the chromophores, accurate description of the spectral features (e.g. absorption and emission), the role of the protein environment, and so on. Specificially, accurate quantum refinement of high-energy intermediates through quantum mechanics/molecular mechanics (QM/MM) and quantum mechanics/polarizable force field (QM/PFF) methods will be developed and applied. Moreover, non-adiabatic QM/MM molecular dynamics simulations and enhanced sampling mehods will be applied to comparatively study different mechanisms of photo-isomerization and conversion in photoreceptor proteins, and elucidate importance of the protein matrix. Insights gained from these investigations will represent an important contribution to the general understanding of nature of light-induced signal transduction. These studies may provide a theoretical guidance for experiments.

在自然界中，能进行光诱导信号传导的光受体蛋白具有非常重要的研究价值。其中，光活性黄蛋白和光敏色素的研究非常活跃。然而，理论研究相对滞后，特别是从原子、分子和长时间尺度上。为了深入理解和研究光受体蛋白的光物理和光化学过程，本项目应用并发展有效的模拟方法：量子力学/分子力学（QM/MM）方法，量子力学/可极化力场（QM/PFF）方法，非绝热QM/MM分子动力学模拟方法，以及与加强采样方法的结合。重点研究光受体蛋白的光生物过程，从原子和分子尺度上来精化晶体结构和光谱精细结构，研究理解生物发色团的光异构化和光诱导转换机制，精细描述光激发和发射等光谱特点，揭示蛋白环境的微观作用本质等。本研究将为光诱导信号传导的理解提供一定的理论基础和指导。

光生物体系和光诱导化学反应是非常重要的和具有挑战性的研究领域。紫外线传感蛋白,荧光RNA,光活性黄蛋白,光敏色素等重要的光生物体系的研究非常活跃。此外，光诱导的多环分子重排反应也是非常有挑战性的，吸引了化学家的广泛关注。本项目应用和发展有效的计算模拟方法来深入研究和理解重要的光生物体系和光诱导反应机理。探究重要光生物体系发色团的光异构化和光诱导转换机制，分析复杂环境的作用，精细描述光激发和发射等光谱特点，以及探讨光诱导多环分子的重排反应机理。这些研究将有利于对光诱导的重要生物和化学反应本质的深入理解。本项目的理论研究工作将为实验研究提供一定的理论基础和指导。我们已经发表三篇高水平SCI文章(2篇JCTC和1篇JACS),并获得第十五届国际量子化学会议的Poster Prize。