Effect of Mn cluster on the formation of superoxide radicals in photoinhibition of photosystem Ⅱ  

作　　者：ZHANG Suping, TU Tiecheng, WENG Jun, PAN Jingxi, XU Chunhe & YAO SideLaboratory of Photosynthesis, Institute of Plant Physiology, Chinese Academy of Sciences, Shanghai 200032, China Laboratory of Radiation Chemistry, Institute of Nuclear Research, Chinese Academy of Sciences, Shanghai 201800, China 

出　　处：《Chinese Science Bulletin》2001年第22期1877-1880,共4页

基　　金：This work was supported by the National Natural Science Foundation of China (Grant No. 39870161) ;the National Key Basic Research and Development Plan (Grant No. G1998010100).

摘　　要：To further realize the action of superoxide radicals (O2 ) in photoinhibition of photosystem II (PS II), we employed 5,5-dimethyl-l-pyrroline-N-oxide (DMPO) as a spin trap, associated with EPK spectroscopy, to study theeffect of illumination time on O2- formation during highlight photoinhibition in PS II membranes and Mn-depleted PS II membranes. Results indicated that the removal of Mn cluster from PS II membranes has a strong influence on the dynamics of superoxide formation. The relative mechanismwas also discussed. These novel findings may further promote the studies of the structure and function of PS II and the mechanism of photoinhibition.To further realize the action of superoxide radicals (O2-) in photoinhibition of photosystem II (PS II), we employed 5,5-dimethyl-l-pyrroline-N-oxide (DMPO) as a spin trap, associated with EPR spectroscopy, to study theeffect of illumination time on O2- formation during highlight photoinhibition in PS II membranes and Mn-depleted PS II membranes. Results indicated that the removal of Mn cluster from PS II membranes has a strong influence on the dynamics of superoxide formation. The relative mechanismwas also discussed. These novel findings may further promote the studies of the structure and function of PS II and the mechanism of photoinhibition.

关 键 词：Mn CLUSTER PHOTOSYSTEM Ⅱ PHOTOINHIBITION superoxide RADICALS EPR. 

分 类 号：Q945.11[生物学—植物学]