Timpmann K E, Taisova A S, Novoderezhkin V I, Fetisova Z G
A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russia.
Biochem Mol Biol Int. 1997 Jun;42(1):21-7. doi: 10.1080/15216549700202391.
In our previous work, we developed, for the first time, a theory of excitation energy transfer within an oligomeric-type light-harvesting antenna and, in particular, within the chlorosome of green bacteria (Biophys.J., 1996, vol.71, pp.995-1010). The theory was recently developed for a new original exciton model of aggregation of chlorosomal pigments, bacteriochlorophylls (BCh1) c/d/e (Biochem, Mol.Biol.Int., 1996, vol.40, No.2, pp. 243-252). In this paper, it was demonstrated with picosecond fluorescence spectroscopy that this theory explains the antenna-size-dependent kinetics of fluorescence decay in chlorosomal antenna, measured for intact cells of different cultures of the green bacterium Chlorobium limicola with different chlorosomal antenna size determined by electron microscopic examination of the ultrathin sections of the cells. According to our model, the energy transfer dynamics within the chlorosome imply the formation of a cylindrical exciton, delocalized over a tubular aggregate of BCh1 c chains, and inductive-resonance-type transfer of such a cylindrical exciton between the nearest tubular BCh1 c aggregates and to BCh1 a of the chlorosome.
在我们之前的工作中，我们首次提出了一种关于寡聚体型光捕获天线内，特别是绿细菌的叶绿体中激发能转移的理论（《生物物理杂志》，1996年，第71卷，第995 - 1010页）。该理论最近针对叶绿体色素细菌叶绿素（BCh1）c/d/e聚集的一种新的原始激子模型得到了进一步发展（《生物化学与分子生物学国际杂志》，1996年，第40卷，第2期，第243 - 252页）。在本文中，通过皮秒荧光光谱法证明，该理论解释了叶绿体天线中荧光衰减的天线尺寸依赖性动力学，这是针对不同培养的绿细菌嗜盐绿菌完整细胞测量得到的，这些细胞的叶绿体天线尺寸通过对细胞超薄切片的电子显微镜检查确定。根据我们的模型，叶绿体中的能量转移动力学意味着形成一个圆柱形激子，它在细菌叶绿素c链的管状聚集体上离域，并且这种圆柱形激子在最近的管状细菌叶绿素c聚集体之间以及向叶绿体的细菌叶绿素a进行感应共振型转移。
