蓝藻(A.variabilis)藻胆体核结构与功能的研究II.变藻蓝蛋白六聚体内能量传递过程的物理机制  

STUDIES ON RELATIONSHIP BETWEEN STRUCTURE AND FUNCTION OF THE PHYCOBILISOME CORE FROM A. varabalis-II. THE EXCITATIONTRANSFER MECHANISM IN ALLOPHYCOCYANIM HEXAMER

作　　者：张景民[1] 赵福利[1] 郑锡光[1] 汪河洲[1] 赵井泉[2] 蒋丽金[2] 

机构地区：[1]中山大学激光与光谱学国家重点实验室 [2]中国科学院感光化学研究所

出　　处：《生物物理学报》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

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.

关 键 词：兰藻 变藻蓝蛋白 六聚体 荧光光谱 能量传递 

分 类 号：Q937[生物学—微生物学] Q949.22