Fluorescence quenching of the phycobilisome terminal emitter LCM from the cyanobacterium Synechocystis sp PCC 6803 detected in vivo and in vitro
Fluorescence quenching of the phycobilisome terminal emitter LCM from the cyanobacterium Synechocystis sp PCC 6803 detected in vivo and in vitro
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DOI：
10.1016/j.jphotobiol.2013.05.014
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发表时间：
2013-08-05
影响因子：
5.4
通讯作者：
Paschenko, Vladimir Z.
中科院分区：
文献类型：
--
作者：
Stadnichuk, Igor N.;Yanyushin, Mikhail F.;Paschenko, Vladimir Z.
在室温下，藻胆体（phycobilisome，PBS）核-膜连接蛋白（core-membrane linker protein，L-CM）的荧光发射可被光活化的橙子类胡萝卜素蛋白（OCP）直接猝灭，表明OCP-L-CM相互作用在蓝藻的非光化学猝灭（non-photochemical quenching，NPQ）中起着重要作用。这一暗示进一步得到以下方面的支持：（i）低温（77 K）荧光发射和激发测量，其显示在光活化OCP存在下属于PBS末端发射体的相应长波长荧光带的特异性淬灭，（ii）通过系统研究野生型和L-CM-1中的荧光猝灭和恢复，更少的细胞的模式蓝藻集胞藻属物种PCC 6803，和（iii）通过脱磷酸化的影响，分离的PBS上的淬灭。使用OCP和APC的晶体结构在计算机中确定PBS内的OCP结合位点和OCP-别藻蓝蛋白（APC）复合物的最可能的几何排列。OCP与PBS核心的几何建模连接与OCP-L-CM相互作用不一致。结果表明，L-CM除了在PBS到反应中心的能量传递和PBS组装中起重要作用外，还在蓝藻的光保护光适应过程中起重要作用。(C)2013作者Elsevier B. V.出版，保留所有权利。
The fluorescence emission of the phycobilisome (PBS) core-membrane linker protein (L-CM) can be directly quenched by photoactivated orange carotenoid protein (OCP) at room temperature both in vitro and in vivo, which suggests the crucial role of the OCP-L-CM interaction in non-photochemical quenching (NPQ) of cyanobacteria. This implication was further supported (i) by low-temperature (77 K) fluorescence emission and excitation measurements which showed a specific quenching of the corresponding long-wavelength fluorescence bands which belong to the PBS terminal emitters in the presence of photoactivated OCP, (ii) by systematic investigation of the fluorescence quenching and recovery in wild type and L-CM-less cells of the model cyanobacterium Synechocystis sp. PCC 6803, and (iii) by the impact of dephosphorylation of isolated PBS on the quenching. The OCP binding site within the PBS and the most probable geometrical arrangement of the OCP-allophycocyanin (APC) complex was determined in silico using the crystal structures of OCP and APC. Geometrically modeled attachment of OCP to the PBS core is not at variance with the OCP-L-CM interaction. It was concluded that besides being a very central element in the PBS to reaction center excitation energy transfer and PBS assembly, L-CM also has an essential role in the photoprotective light adaptation processes of cyanobacteria. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.