Department of Chemical Sciences, University of Padova, via F. Marzolo 1, 35131, Padova, Italy.
Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124, Pisa, Italy.
Nat Commun. 2018 Aug 8;9(1):3160. doi: 10.1038/s41467-018-05596-5.
The subtle details of the mechanism of energy flow from carotenoids to chlorophylls in biological light-harvesting complexes are still not fully understood, especially in the ultrafast regime. Here we focus on the antenna complex peridinin-chlorophyll a-protein (PCP), known for its remarkable efficiency of excitation energy transfer from carotenoids-peridinins-to chlorophylls. PCP solutions are studied by means of 2D electronic spectroscopy in different experimental conditions. Together with a global kinetic analysis and multiscale quantum chemical calculations, these data allow us to comprehensively address the contribution of the potential pathways of energy flow in PCP. These data support dominant energy transfer from peridinin S to chlorophyll Q state via an ultrafast coherent mechanism. The coherent superposition of the two states is functional to drive population to the final acceptor state, adding an important piece of information in the quest for connections between coherent phenomena and biological functions.
生物光捕获复合物中类胡萝卜素到叶绿素能量流的机制细节仍未完全被理解，尤其是在超快过程中。在这里，我们聚焦于天线复合物别藻蓝蛋白（PCP），它以其从类胡萝卜素别藻蓝蛋白到叶绿素的激发能量转移的显著效率而闻名。通过在不同实验条件下的二维电子光谱研究 PCP 溶液。这些数据与全局动力学分析和多尺度量子化学计算相结合，使我们能够全面解决 PCP 中能量流潜在途径的贡献。这些数据支持通过超快相干机制将能量从别藻蓝蛋白 S 转移到叶绿素 Q 态的主要转移。这两个态的相干叠加对于驱动到最终受体态的种群是功能性的，为相干现象与生物功能之间的联系提供了重要信息。
