期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2018
卷号:115
期号:41
页码:E9523-E9531
DOI:10.1073/pnas.1806597115
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:An important determinant of crop yields is the regulation of photosystem II (PSII) light harvesting by energy-dependent quenching (qE). However, the molecular details of excitation quenching have not been quantitatively connected to the fraction of excitations converted to chemical energy by PSII reaction centers (PSII yield), which determines flux to downstream metabolism. Here, we incorporate excitation dissipation by qE into a pigment-scale model of excitation transfer and trapping for a 200 × 200-nm patch of the grana membrane. We show that excitation transport can be rigorously coarse grained to a 2D random walk with an excitation diffusion length determined by the extent of quenching. We present an alternative method for analyzing pulse amplitude-modulated chlorophyll fluorescence measurements that incorporates the effects of a variable excitation diffusion length during qE activation.
关键词:photosynthesis ; photosystem II ; nonphotochemical quenching ; excitation energy transport ; multiscale model