螺旋藻变藻蓝蛋白内能量传递机制的研究  

PICOSECOND ENERGY TRANSFER BETWEEN CHROMOPHORESIN ALLOPHYCOCYANINS

作　　者：王慧[1] 赵井泉[2] 蒋丽金[2] 

机构地区：[1]清华大学环境科学与工程系 [2]中科院感光化学所

出　　处：《生物物理学报》1999年第2期386-392,共7页Acta Biophysica Sinica

基　　金：国家自然科学基金

摘　　要：利用ｐｓ时间分辨荧光光谱技术研究两种不同结构变藻蓝蛋白复合物ＡＰ６６５和ＡＰ６６０内能量传递过程，讨论了变藻蓝蛋白三聚体和单体内激发态作用机制。结果表明，ＡＰＣ单体只有一个短寿命（７５ｐｓ），来源于其两个亚基α８４／β８４间能量传递过程，另一长寿命（１０８０ｐｓ）是β８４基态恢复的平衡时间。两种ＡＰＣ三聚体均含有一个短寿命组分，从１６ｐｓ（ＡＰ６６０）到４８ｐｓ（ＡＰ６６５），它们来源于三聚体内互为Ｃ３对称单体内α８４／β８４间能量传递过程。ＡＰ６６０由于结构对称性低出现的短寿命组分（１０６ｐｓ），可指认为低对称单体的α８４／β８４之间能量传递时间常数。连接多肽对ＡＰＣ三聚体性质的影响明显地表现在其荧光衰减动力学过程中。Ultrafast time-resolved fluorescence spectra were used to study the energy transfer kinetics of AP660 and AP665 from Cynobacteria Spirulina Platensis. Both excited state energy grades and energy transfer time constants in these APCs in monomeric as wellas trimeric aggregation states were also discussed. A single lifetime component (75ps) was found in energy transfer process of αAP/βAP in AP660 and AP665 monomers,while 16ps in AP665 and 48ps in AP660 were observed and attributed to the same energy transfer between αAP/βAP with C3 symmetry in the same monomers. Lack of the linker polypeptide in AP660 gave rise to a heterogeneity in the chromophore conformation and chromophore-chromophore interactions, another fast lifetime(106ps) was also found.

关 键 词：螺旋藻 变藻蓝蛋白 连接多肽 荧光光谱 能量传递 

分 类 号：Q949.22[生物学—植物学] Q937