Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
Department of Chemistry, Princeton University , Washington Road, Princeton, New Jersey 08544, United States.
Chem Rev. 2017 Jan 25;117(2):249-293. doi: 10.1021/acs.chemrev.6b00002. Epub 2016 Jul 18.
The process of photosynthesis is initiated by the capture of sunlight by a network of light-absorbing molecules (chromophores), which are also responsible for the subsequent funneling of the excitation energy to the reaction centers. Through evolution, genetic drift, and speciation, photosynthetic organisms have discovered many solutions for light harvesting. In this review, we describe the underlying photophysical principles by which this energy is absorbed, as well as the mechanisms of electronic excitation energy transfer (EET). First, optical properties of the individual pigment chromophores present in light-harvesting antenna complexes are introduced, and then we examine the collective behavior of pigment-pigment and pigment-protein interactions. The description of energy transfer, in particular multichromophoric antenna structures, is shown to vary depending on the spatial and energetic landscape, which dictates the relative coupling strength between constituent pigment molecules. In the latter half of the article, we focus on the light-harvesting complexes of purple bacteria as a model to illustrate the present understanding of the synergetic effects leading to EET optimization of light-harvesting antenna systems while exploring the structure and function of the integral chromophores. We end this review with a brief overview of the energy-transfer dynamics and pathways in the light-harvesting antennas of various photosynthetic organisms.
光合作用的过程始于光吸收分子（发色团）对阳光的捕获，这些分子还负责将激发能随后传递到反应中心。通过进化、遗传漂变和物种形成，光合生物已经发现了许多用于收集光的解决方案。在这篇综述中，我们描述了吸收能量的基本光物理原理，以及电子激发能量转移（EET）的机制。首先，我们介绍了存在于光捕获天线复合物中的单个色素发色团的光学性质，然后我们研究了色素-色素和色素-蛋白相互作用的集体行为。能量转移的描述，特别是多色素天线结构，取决于空间和能量景观，这决定了组成色素分子之间的相对耦合强度。在文章的后半部分，我们以紫色细菌的光捕获复合物为例，重点介绍了协同效应，这些协同效应导致光捕获天线系统的 EET 优化，同时探索了整体色素的结构和功能。最后，我们简要概述了各种光合生物光捕获天线中的能量转移动力学和途径。
