菠菜PSII核心复合物激发能传递与温度的关系

采用基于延时分次扫描单光子计数器为探测装置的皮秒时间分辨荧光光谱测试系统研究了菠菜光系统(PSⅡ)核心复合物光能传递与温度的关系.分别对PSII核心复合物样品在20℃、42℃、48℃下做温浴处理,然后以脉宽为120 ps,重复率为4MHz,波长为514nm的Ar+激光作为光源分别激发处理后样品的荧光.通过对测量结果进行数据处理,分析比较发现:同一温度下,呈荧光带的激发能传递速度比副荧光带处的快;同一波长下,慢组分的时间常量随温度升高而变慢,而快速组分的时间常数则变化不大;做42℃温浴处理的样品接近于蛋白质解体的临界状态.

THE VARIETY OF EXCITED ENERGY TRANSFER WITH TEMPERATURE ABOUT CORE COMPLEX OF SPINACH IN PHOTOSYSTEM Ⅱ

Fluorescence spectroscopic and time properties of isolated core complex of spinach in photosystem II, which is treated with temperature at 20℃?42℃?48℃ five minutes, is investigated using picosecond resolving of fluorescence spectrum measurement with delay frame scanning single photon counting technique. The samples are excited by Ar + laser with 514nm (wavelength), 120ps (width of pulse) and 4MHz (pulse repetition). The varieties of light energy transfer with temperature are compared in detail. The conclusions are that: 1) at the same temperature, the velocity of the excited energy transferring is quicker with the main fluorescence band than subrdinate fluorescence band;2) at the same wavelength, the time constants of the slowest component at lower temperature is bigger than the higher temperature’s and the time constants of quicker components is not sensitive with the temperature; 3) some special evidence at 420 C have been found especially CP47, it might have been a critical temperament which the protein complex are disassembly.