摘要
以变藻蓝蛋白的晶体结构和光谱性质为基础，利用密度矩阵理论对变藻蓝蛋白六聚体内的激发能传递物理机制进行分析，并利用时间分辨荧光光谱技术对其能量传递途径进行实时探测。结果表明：在变藻蓝蛋白六聚体内，色素对（毗邻单体上的色素αｉ８４βｊ８４，其中ｊ＝ｉ±１，和β＊ＬＣＭ４２）内的能量传递服从激子偶极－偶极相互作用机制；而色素对之间的能量传递机制则为Ｆｒｓｔｅｒ偶极－偶极相互作用机制，并且其能量传递途径分为两类：（１）．两个变藻蓝蛋白三聚体之间色素对的能量传递，其时间常数大约为１５ｐｓ左右；（２）．同一变藻蓝蛋白三聚体内色素对间的能量传递，在ＡＰＩＩ三聚体内，其能量传递时间大约为４５ｐｓ左右，而在ＡＰＩ三聚体内，其能量传递时间常数为４５ｐｓ和６５ｐｓ。
In this work, we provided the excitation energy transfer mechanism in allophycocyanin hexamer with density matrix theory and time-resolved fluorescence experiments. The data showed that the excitation transfer mechanism in allophycocyanin hexamer could be described as followings: The excitation transfers occurring within the chromophores of the adjacent monomers of same trimer may obey the exciton-coupling mechanism. However, those of occuring between chromophore pairs may obey the Forster mechanism. The excitation transfer constant between two APC trimers is ca. 16ps and that of between two dimers in the same APCII trimer is about 40ps while those of in API trimer were characterized by 40 and 65ps.
出处
《生物物理学报》
CSCD
北大核心
1999年第2期393-399,共7页
Acta Biophysica Sinica
基金
国家自然科学基金
广东省自然科学基金
广东省博士后科学基金
关键词
兰藻
变藻蓝蛋白
六聚体
荧光光谱
能量传递
Allophycocyanin hexamer
Time-resolved fluorescence anisotropy
Energy transfer
