Structural dynamics and photoinduced electron transfer

结构动力学和光致电子转移

• 批准号: EP/R029687/1
• 负责人: A Vlcek
• 金额: $ 84.73万
• 依托单位: Queen Mary University of London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FR029687%2F1
• 关键词: Structural; dynamics; photoinduced; electron; transfer

Our life closely depends on light: vision provides us with information on the world around us while photosynthesis supplies us with food, as well as energy that was deposited over millions of years in fossil fuels. Photosynthesis employs a flow of electrons through proteins driven by sunlight and many researchers are trying to replicate it and produce fuels from abundant clean sources in artificial systems. Electron transfer also underlies many enzymatic reactions as well as respiration. Sequential transfer of electrons through chains of aromatic amino acids (tryptophan, tyrosine) was recently suggested to play a protective role in enzymes that use molecular oxygen to oxidize organic compounds in our bodies.Chemical reactions, including electron transfer, are too often explained in terms of static molecular or protein structures. However, life and chemistry are highly dynamic; molecules as well as their environment are perpetually in motion. Indeed, Richard Feynman famously wrote "everything that is living can be understood in terms of the jiggling and wiggling of atoms". In our work, we will focus on this aspect and try to understand the relation between structural fluctuations and electron transfer. We will study proteins bearing photoactive groups that are capable of inducing transfer of electrons across the protein upon irradiation with visible or ultraviolet light. We will measure how such photoactive assemblies and surrounding water molecules fluctuate in time and relate these structural dynamics with the rates, yields, and directionality of phototriggered electron transfer. Among several protein systems, we will also study proteins (azurins) with several aromatic amino acid groups that can themselves undergo electron transfer, while their mutual distance and orientation fluctuate in time. These investigations will tell us how to design photocatalytic systems for artificial photosynthesis to generate fuels or specialty chemicals, as green plants do. In particular, engineering aromatic amino acid chains into proteins is a promising way to strongly accelerate electron transfer in the desired direction.Time resolved vibrational spectroscopy methods are perfectly suited for such dynamics studies. Infrared or Raman spectra, which report on molecular vibrational motions, are measured as a function of time after irradiation with short laser pulses of light that trigger both structural relaxation and electron transfer. Shifts and intensity changes of spectral features, together with the emergence of new ones, will simultaneously reveal the nature and rates of structural changes and electron transfer processes. Sophisticated data analysis and theoretical calculations will enable interpretation of experimental results and building up a unifying mechanistic picture of interrelated electron transfer and structural dynamics. UK operates a world leading facility in the field of time resolved vibrational spectroscopy at the Rutherford Appleton Laboratory in Oxfordshire, providing a unique opportunity to carry out the proposed research at the highest experimental level.

我们的生活密切依赖于光：视觉为我们提供了关于周围世界的信息，而光合作用为我们提供了食物，以及数百万年来储存在化石燃料中的能量。光合作用利用了在阳光驱动下穿过蛋白质的电子流，许多研究人员正试图复制这一过程，并在人工系统中利用丰富的清洁来源生产燃料。电子转移也是许多酶反应和呼吸作用的基础。最近，电子通过芳香氨基酸(色氨酸、酪氨酸)链的顺序转移被认为在利用分子氧在我们体内氧化有机化合物的酶中起到保护作用。化学反应，包括电子转移，太多地被用静态分子结构或蛋白质结构来解释。然而，生命和化学是高度动态的；分子和它们的环境是永远在运动的。事实上，理查德·费曼曾写过一句名言：“一切生物都可以用原子的摆动来理解”。在我们的工作中，我们将专注于这一方面，并试图了解结构涨落与电子转移之间的关系。我们将研究含有光活性基团的蛋白质，这些基团能够在可见光或紫外光照射下诱导电子通过蛋白质传递。我们将测量这种光活性组件和周围的水分子如何随时间波动，并将这些结构动力学与光触发电子转移的速率、产量和方向性联系起来。在几个蛋白质体系中，我们还将研究具有几个芳香氨基酸基团的蛋白质(天青素)，这些蛋白质本身可以进行电子转移，而它们之间的相互距离和取向随着时间的变化而波动。这些研究将告诉我们如何设计人工光合作用的光催化系统，以产生燃料或特殊化学品，就像绿色植物一样。特别是，将芳香族氨基酸链工程到蛋白质中是一种很有希望的方法，可以强烈地加速电子在所需方向上的转移。时间分辨振动光谱方法非常适合于这样的动力学研究。报告分子振动运动的红外或拉曼光谱是在短激光脉冲照射后作为时间函数进行测量的，该短激光脉冲同时触发结构驰豫和电子转移。光谱特征的移动和强度变化，以及新的特征的出现，将同时揭示结构变化和电子转移过程的性质和速率。复杂的数据分析和理论计算将能够解释实验结果，并建立相互关联的电子转移和结构动力学的统一机制图。英国在牛津郡的卢瑟福·阿普尔顿实验室运营着时间分辨振动光谱学领域的世界领先设施，为在最高实验水平上开展拟议的研究提供了独特的机会。

项目成果

Optical and Infrared Spectroelectrochemical Studies of CN-Substituted Bipyridyl Complexes of Ruthenium(II).

CN 取代的钌 (II) 联吡啶配合物的光学和红外光谱电化学研究。

• DOI: 10.1021/acs.inorgchem.0c03579
• 发表时间: 2021
• 期刊: Inorganic chemistry
• 影响因子: 4.6
• 作者: Taylor JO

Nonadiabatic excited-state dynamics of ReCl(CO)3(bpy) in two different solvents.

ReCl(CO)3(bpy) 在两种不同溶剂中的非绝热激发态动力学。

• DOI: 10.1039/d2cp02981b
• 发表时间: 2022
• 期刊: PCCP
• 作者: Šrut A

Tryptophan to Tryptophan Hole Hopping in an Azurin Construct.

• DOI: 10.1021/acs.jpcb.3c06568
• 发表时间: 2024-01-11
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY B
• 影响因子: 3.3
• 作者: Melcak, Martin;Sebesta, Filip;Heyda, Jan;Gray, Harry B.;Zalis, Stanislav;Vlcek, Antonin
• 通讯作者: Vlcek, Antonin

Time-Resolved Femtosecond Stimulated Raman Spectra and DFT Anharmonic Vibrational Analysis of an Electronically Excited Rhenium Photosensitizer.

• DOI: 10.1021/acs.jpca.9b10840
• 发表时间: 2020-01
• 期刊: The journal of physical chemistry. A
• 作者: Martin Pižl;A. Picchiotti;M. Rebarz;Nils Lenngren;Yingliang Liu;S. Záliš;M. Kloz;A. Vlček

Hole Hopping Across a Protein-Protein Interface.

蛋白质-蛋白质界面上的空穴跳跃。

• DOI: 10.1021/acs.jpcb.8b11982
• 发表时间: 2019
• 期刊: The journal of physical chemistry. B
• 作者: Takematsu K