温度升高对PSⅡ中CP47和CP47/D_1/D_2/Cyt b_(559)Chla能量传递的影响

Effect of temperature ascending on energy transfer of Chla in CP47 and CP47/D_1/D_2/Cyt b_(559) of PSⅡ

采用激励光源为 4 MHz、5 1 4 .5 nm的延时分幅扫描单光子计数荧光装置对从菠菜中分离提纯的核心天线CP4 7和 CP4 7/D1 /D2 /Cyt b559复合物的 Chla的能量传递进行了研究 ,得到经 2 0℃、4 2℃和 4 8℃处理后的最大峰值处的时间常量 .分析认为 CP4 7中 ,2 0～ 4 2℃之间的温度对蛋白质空间结构的改变较小 ,Chla分子之间的能量传递受到微小的影响 ,而 4 2～ 4 8℃之间的温度引起较大的蛋白质空间结构改变 ,明显地影响了其中 Chla分子间的能量传递 .在 PS CP4 7/D1 /D2 /Cyt b559复合物中 ,处理温度的升高使 CP4 7/D1 /D2 /Cyt b559复合物的二级结构、色素分布的空间位置发生变化 ,从而影响了 CP4 7/D1 /D2 /Cyt b559复合物中 Chla的能量传递以及电荷重组 ,4 2℃已对其造成影响 ,而 4

Effect of temperature ascending on energy transfer of Chla in PSⅡ inner antenna CP47 and reaction center CP47/D 1/D 2/Cyt b 559 complex were studied by the delay papting frame scanning single photon counting fluorescence spectroscopy. CP47 and CP47/D 1/D 2/Cyt b 559 complex were treated at 20℃,42℃and 48℃ respectively. The fluorescence lifetime at maximum peak per treating temperature were gained. It was analysised that in CP47, the protein conformation and energy transfer between Chla molecules were affected a little between 20℃ and 42℃. While, between 42℃ and 48℃, they had distinct changes. In CP47/D 1/D 2/Cyt b 559 , the change of protein comformation and spatial orientation of CP47/D 1/D 2/Cyt b 559 complex by ascending temperature influenced the energy transfer and charge recombination. There were more obvious changes at 42℃ and the most obvious changes at 48℃.