Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA.
Molecules. 2018 Oct 10;23(10):2589. doi: 10.3390/molecules23102589.
Multichromophoric interactions control the initial events of energy capture and transfer in the light harvesting peridinin-chlorophyll protein (PCP) from marine algae dinoflagellates. Due to the van der Waals association of the carotenoid peridinin (Per) with chlorophyll in a unique 4:1 stoichiometric ratio, supramolecular quantum mechanical/molecular mechanical (QM/MM) calculations are essential to accurately describe structure, spectroscopy, and electronic coupling. We show that, by enabling inter-chromophore electronic coupling, substantial effects arise in the nature of the transition dipole moment and the absorption spectrum. We further hypothesize that inter-protein domain Per-Per interactions are not negligible, and are needed to explain the experimental reconstruction features of the spectrum in wild-type PCP.
多发色团相互作用控制了海洋藻类甲藻的光捕获和能量转移过程中最初的事件，该过程涉及的是多甲藻叶黄素-叶绿素蛋白（PCP）。由于类胡萝卜素叶黄素（Per）与叶绿素之间以独特的 4:1 化学计量比范德华缔合，因此超分子量子力学/分子力学（QM/MM）计算对于准确描述结构、光谱和电子耦合至关重要。我们表明，通过使发色团之间的电子耦合成为可能，会在跃迁偶极矩和吸收光谱的性质上产生显著的影响。我们进一步假设，蛋白域间的 Per-Per 相互作用不可忽略，并且需要解释野生型 PCP 中实验重建光谱的特征。
