在83 K和160 K两个温度下,通过激发波长对荧光发射谱的影响研究了光系统Ⅱ中核心复合物的荧光光谱特性.用不同波长的光激发,核心复合物的发射谱的最大发射峰值不变,用480、489、495和507 nm的光分别激发核心复合物,其光谱最大峰值处的荧光强度随不同激发波长下β-胡萝卜素分子的吸收强度的增大而降低,在长波长区域光谱的变化依赖于首先被激发的色素分子.所以,激发波长的不同影响着核心复合物中能量传递的途径.通过高斯解析,分析出核心复合物中至少存在有7组叶绿素a组分,它们是Chl a660,Chl a670,Chl a680,Chl a682,Chl a684,Chl a687和Chl a690.%Spectroscopic properties within the core complex of photosystem Ⅱ were investigated by studying the influence of the wavelength of excitation on the fluorescence emission spectrum. At two temperatures, when the core complex of PSⅡ isolated from spinach was excited at six different excitation wavelengths ranging from 436nm to 520 nm, there is no difference in the maxima of the emission spectra of the core complex, and when the core complex was excited at 480, 489, 495 and 507 nm respectively, fluorescence intensities of maxima decrease with increasing of the absorbance of the β-carotene mol ecules at the four excitation wavelengths. The extent of change of the shoulder of the spectra beyond 700 nm depends on the kind of pigment molecule excited. The excitation wavelength can influence the way of energy transfer in the core complex of photosystem Ⅱ. By Gaussian deconvolution analysis, at least seven groups of chlorophyll a molecules were discovered. They are Chl a660, Chl a670, Chl a680, Chl a682, Chl a684, Chl a687 and Chl a690.
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