藻类捕光天线系统:结构与功能的统一

Algal light-harvesting system:Linkage of structures and functions by using structural biology

藻类是光合自养的水生孢子植物,为了适应水下弱光的特殊生境,藻类捕光天线历经亿万年的进化,形成了特殊的结构与功能。从发现藻类捕光天线的存在到至今的70多年间,其结构解析技术的发展共经历了4个阶段:首先是利用生化及普通光谱技术研究结构组成(1950−1980年);其次是利用X-ray晶体学技术研究局部精细结构(1980年至今);再次是利用电镜技术研究完整的粗略结构(1980−2010年);最后是近10年来利用冷冻电镜技术研究完整的精细结构(2010年至今)。目前以蓝藻、红藻、绿藻和硅藻为主的藻类捕光天线复合体完整的精细结构均已被解析,仅2019年就有10余种精细结构被发现。藻类捕光天线系统结构生物学的研究,不仅搭建了对结构与功能统一认识的桥梁,而且为深入揭示藻类光合作用高效能量传递机制奠定了坚实的结构基础。将藻类捕光天线系统结构和功能统一起来,进一步研究对光环境的适应性成为未来的重点,并将为藻类捕光天线蛋白在光电器件领域的应用提供充分的科学依据。

Algae are general term of a large group of photoautotrophic aquatic sporophytes.Along with the long earth history,the algal light-harvesting antenna has evolved special structure and function,to adapt to low-light underwater environment.Since the algal light-harvesting antennas were first discovered 70 years ago,the progress of structural analysis can be divided into four stages.The first stage was from 1950 to 1980,and effects were focused on studying the structural composition of light-harvesting antenna through biochemical and spectral techniques.The second stage was from 1980 to the present,and X-ray crystallization becomes a primary tool to study the partial fine-structure of the complete complex.The third stage was from 1980 to 2010.In this stage,complete contour structure can be studied by using electron microscope(EM).The fourth stage is from 2010 to the present,and the use of cryo-EM technology to studied intact fine-structure has brought the blowout period of structural analysis in recent year.With the rapid development of cryo-EM technology,a variety of complete fine-structures of algal lightharvesting antenna complexes have been analyzed,including cyanobacteria,red algae,green algae,and diatoms.Specifically,in 2019,multiple super-molecular complex structures of algal light-harvesting antenna were resolved.This breakthrough provides us valuable structure information for the study of energy transfer and the unified relationship between structure and function.However,the synthetic understanding of the relationship between the structure,function,environment,and applications of algal light-harvesting antennas is still preliminary,compared to the huge demand of solar energy utilization from bio-materials.Therefore,further research on the light adaptability of light-harvesting proteins has become the focus of the future,and will provide a sufficient scientific basis for the application of algal light-harvesting antenna proteins in the field of photoelectric devices.