摘要
在植物中,光合作用的高效光电转化效率归因于色素蛋白复合体中所建立的强大捕光网络与灵活的能量转移机制.对色素蛋白复合体结构与功能的解析是光合作用研究中的重要方向,对人工光合作用研究和能源可持续发展战略具有指导意义.随着冷冻电子显微镜的快速发展,大量复合体的精密结构得以解析.冷冻光学(光谱)显微镜是冷冻电子显微镜的重要互补技术,发展至今已有约35年的历史.该方法通过光谱特征可精确识别多种色素蛋白复合体,而低温成像不仅有效地抑制了单个复合体或细胞样品的光损伤,还限制了复合体中色素间的uphill能量转移,从而提高荧光量子收率.冷冻光学显微镜不仅成为表征单个蛋白质的结构动态与捕光功能的有力工具;还为可视化和定量复杂的光合成分在细胞体内的空间分布提供了可能性.因此,该技术的应用极大地发展了在微观尺度下分析色素蛋白结构与功能的研究领域,这对于光合作用研究体系的推进具有重大意义.本文从单分子光谱与单细胞光谱技术两方面总结了冷冻光谱显微镜技术在自然光合作用中的主要应用与取得的成果,其中包括探究色素蛋白复合体的捕光功能与蛋白质动态的关联,复合体中能量异质性的表征,在细胞体内可视化光合蛋白的能量调控机制等.
Efficient photosynthesis reaction is attributed to the flexible energy regulation of two important pigmentprotein complexes,i.e.photosystem II(PSII)and photosystem I(PSI).Cryogenic spectral microscopy provides information about the spatial distribution and physiological functional states of photosynthetic components in photosynthetic organisms.Under low temperatures,the uphill energy transfer between pigments is efficiently suppressed so that the temperature-dependent PSI can be well analyzed.Therefore,a cryogenic spectral microscope allows us to discuss the physiological events surrounding PSII and PSI in the independent microscopic zones.This technique can be used to complement the insufficiencies of cryogenic electron microscopy and atomic force microscopy in analyzing the photophysics and photochemistry of photosynthetic species.Historically,cryogenic optical microscopes originated from the desire for single-molecule spectroscopy detection.So far,the combination of optical microscopies and various spectroscopic techniques has expanded the possibility of studying photosynthesis from multiple perspectives.In this paper,the important and recent progress of cryogenic spectral microscopy in the field of natural photosynthesis research is reviewed from two aspects:single-molecule spectroscopy and single-cell spectroscopy,and the advantages of this technique in clarifying the correlation between structure variability and function of pigment-protein complexes,as well as the physiological responses of photosynthetic organisms to variable environments,are also illustrated.
作者
张先骏
Zhang Xian-Jun(Department of Chemistry,Tohoku University,Sendai 980-8578,Japan;Department of Chemistry,Massachusetts Institute of Technology,Cambridge,MA 02139,USA)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2024年第22期23-48,共26页
Acta Physica Sinica
关键词
光合作用
光捕获
能量调控
冷冻光学显微镜
单分子光谱
photosynthesis
light-harvesting
energy regulation
cryogenic optical microscope
single-molecule spectroscopy
