嗜热蓝藻层理鞭枝藻（Mastigocladus laminosus）藻胆体在解离过程中荧光发射光谱和光能传递的研究

研究了层理鞭枝藻藻胆体在不同浓度磷酸缓冲溶液中解离过程中荧光发射光谱的变化和光能传递。完整藻胆体的７７Ｋ荧光光谱中只有一个峰，位于６８５ｎｍ它是末端发射体（核心－膜连接多肽和别藻蓝蛋白－Ｂ）的荧光峰。部分解离藻胆体的荧光光谱的主峰位移至６５２ｎｍ：次峰位于６８５ｎｍ；６６０ｎｍ为一弱荧光发射肩。它们依次为Ｃ－藻蓝蛋白，末端发射体和别藻蓝蛋白的荧光。严重解离藻胆体的荧光主峰移６４４ｎｍ；次峰由６８５ｎｍ移至６８２ｎｍ；６６０ｎｍ荧光发射肩消失。这表明Ｃ－藻蓝蛋白所捕获的光能已不能传递给别藻蓝蛋白，但可传递给末端发射体洞时又表明Ｃ－藻蓝蛋白不仅与别藻蓝蛋白相连接而且还与末端发射体相连接。提出该藻胆体光能传递链如下：核心－膜连接多肽藻红蓝蛋白→Ｃ－藻蓝蛋白→别藻蓝蛋白别藻蓝蛋白－Ｂ

FLUORESCENCE EMISSION AND ENERGY TRANSFER OF PHYCOBILISOMES FROM THERMOPHILIC CYANOBACTERIUM MASTIGOCLADUS LAMINOSUS DURING DISSOCIATION

Changes in fluorescence emission spcetra of phycobilisomes from Mastigocladus laminosus durihg dissociation in phosphate buffer of various molarity were studied. The 77k fluorescence emission spectrum of intact phycobolisomes showed one peak: F685, characterstic of termnal emitters. That of partial dissociated phycobilisomes indicated three bands: F652, F660 and F685, characteristic of C-phycocyanin (C-PC), allophycocyainn (APC) and torminal emitters respectively. Of the three bands, F652 was a main peak, F685 was a second peak and F660was a weak shoulder. When phycobilisomes were severely dissociated, the main peak shifted to 644nm; while F683, which originated from terminal emitters, became a weak peak instead of F685, F660 disappeared. We suggest that in these phycobilisomes some C-PC contact with APC and other contact with terminal terminal, an energy transfer chain shown as follows: