高等植物光系统超复合体II的能量功能效率
Efficiency of energy funneling in the photosystem II supercomplex of higher plants
摘要：
光合多蛋白质网络中能量传递特性的研究有助于深入了解其设计原理。本文讨论了高等植物光合机构中最大的功能单元--光系统II（PS-II）C $_2$ S $_2$ M $_2$超复合体的激子能量传递机制。尽管C $_2$ S $_2$ M $_2$中缺乏决定性的能量梯度，我们表明，能量转移是由弛豫指向低能态。C $_2$ S $_2$ M $_2$没有被组织成形成具有严格的能量向下转移的途径，这对转移效率、转移途径和转移限制步骤具有直接的后果。激子动力学对小的结构变化很敏感，例如，由振动坐标的重组引起的结构变化。为了将重组过程中，我们的数值模拟，我们超越速率方程，并使用分层耦合运动方程的方法（HEOM）。虽然从外周天线到反应中心附近的蛋白质的转移发生在更快的时间尺度上，但能量转移到RC核心的最后一步相当慢，因此是转移链中的限制步骤。我们的研究结果表明，PS-II超复合物的结构保证光保护，而不是优化效率。
英文摘要：
The investigation of energy transfer properties in photosynthetic multi-protein networks gives insight into their underlying design principles.Here, we discuss excitonic energy transfer mechanisms of the photosystem II (PS-II) C$_2$S$_2$M$_2$ supercomplex, which is the largest isolated functional unit of the photosynthetic apparatus of higher plants.Despite the lack of a decisive energy gradient in C$_2$S$_2$M$_2$, we show that the energy transfer is directed by relaxation to low energy states. C$_2$S$_2$M$_2$ is not organized to form pathways with strict energetic downhill transfer, which has direct consequences on the transfer efficiency, transfer pathways and transfer limiting steps. The exciton dynamics is sensitive to small structural changes, which, for instance, are induced by the reorganization of vibrational coordinates. In order to incorporate the reorganization process in our numerical simulations, we go beyond rate equations and use the hierarchically coupled equation of motion approach (HEOM). While transfer from the peripherical antenna to the proteins in proximity to the reaction center occurs on a faster time scale, the final step of the energy transfer to the RC core is rather slow, and thus the limiting step in the transfer chain. Our findings suggest that the structure of the PS-II supercomplex guarantees photoprotection rather than optimized efficiency.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
