EXCITATION-ENERGY TRANSFER FROM PHYCOBILISOMES TO PHOTOSYSTEM-I IN A CYANOBACTERIUM
EXCITATION-ENERGY TRANSFER FROM PHYCOBILISOMES TO PHOTOSYSTEM-I IN A CYANOBACTERIUM
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DOI：
10.1016/0167-4838(92)90483-t
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发表时间：
1992-06-19
期刊：
影响因子：
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通讯作者：
MULLINEAUX, CW
中科院分区：
文献类型：
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作者：
MULLINEAUX, CW
使用闪光诱导的700 nm吸光度变化来确定蓝细菌Synechococcus 6301全细胞中光系统I的吸收截面。通过改变激发闪光的波长，构建了PS I的激发光谱。PS I在暗适应（光状态2）细胞中的激发光谱显示对应于藻胆素的吸收的大峰。此峰在无藻胆体的类囊体膜中不存在。光状态1的适应降低了PS I对藻胆素吸收光的吸收截面，但对叶绿素吸收光的影响不大。PS II反应中心的关闭对PS I的吸收截面没有可检测的影响，这表明从藻胆体到PS I的能量传递是直接的，而不是从PS II溢出。有人提出，在适应光状态2的细胞中，一定比例的藻胆体与PS I特异性相关。
Flash-induced absorbance changes at 700 nm were used to determine the absorption cross-section of Photosystem I in whole cells of the cyanobacterium Synechococcus 6301. By varying the wavelength of the excitation flash an excitation spectrum for PS I was constructed. The excitation spectrum for PS I in dark-adapted (light-state 2) cells shows a large peak corresponding to absorbance by phycobilins. This peak is absent in phycobilisome-free thylakoid membranes. Adaptation to light-state 1 decreases the absorption cross-section of PS I with phycobilin-absorbed light, but has little effect with chlorophyll-absorbed light. The closure of PS II reaction centres has no detectable effect on the absorption cross-section of PS I, suggesting that energy transfer from phycobilisomes to PS I is direct rather than spillover from PS II. It is proposed that, in cells adapted to light-state 2, a proportion of phycobilisomes are specifically associated with PS I.