光系统II的原初电子供体P680的多聚体模型。
A multimer model for P680, the primary electron donor of photosystem II.
作者信息
Durrant J R, Klug D R, Kwa S L, van Grondelle R, Porter G, Dekker J P
机构信息
Centre for Photomolecular Sciences, Department of Biochemistry, Imperial College, London, United Kingdom.
出版信息
Proc Natl Acad Sci U S A. 1995 May 23;92(11):4798-802. doi: 10.1073/pnas.92.11.4798.
We consider a model of the photosystem II (PS II) reaction center in which its spectral properties result from weak (approximately 100 cm-1) excitonic interactions between the majority of reaction center chlorins. Such a model is consistent with a structure similar to that of the reaction center of purple bacteria but with a reduced coupling of the chlorophyll special pair. We find that this model is consistent with many experimental studies of PS II. The similarity in magnitude of the exciton coupling and energetic disorder in PS II results in the exciton states being structurally highly heterogeneous. This model suggests that P680, the primary electron donor of PS II, should not be considered a dimer but a multimer of several weakly coupled pigments, including the pheophytin electron acceptor. We thus conclude that even if the reaction center of PS II is structurally similar to that of purple bacteria, its spectroscopy and primary photochemistry may be very different.
我们考虑了一种光系统II（PS II）反应中心模型，其中其光谱特性源于大多数反应中心二氢卟酚之间的弱（约100 cm⁻¹）激子相互作用。这样的模型与紫色细菌反应中心的结构相似，但叶绿素特殊对的耦合有所减弱。我们发现该模型与许多关于PS II的实验研究一致。PS II中激子耦合大小和能量无序性的相似性导致激子态在结构上高度不均匀。该模型表明，PS II的初级电子供体P680不应被视为二聚体，而应是包括去镁叶绿素电子受体在内的几种弱耦合色素的多聚体。因此我们得出结论，即使PS II的反应中心在结构上与紫色细菌的相似，但其光谱学和初级光化学可能非常不同。
Zotero 插件