Kim Eunchul, Lee Daekyung, Sakamoto Souichi, Jo Ju-Yeon, Vargas Mauricio, Ishizaki Akihito, Minagawa Jun, Kim Heetae
Division of Environmental Photobiology, National Institute for Basic Biology, Okazaki 444-8585, Japan.
Basic Biology Program, Graduate Institute for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan.
Sci Adv. 2025 May 9;11(19):eads0327. doi: 10.1126/sciadv.ads0327.
In green plants, chlorophyll a and chlorophyll b are the predominant pigments bound to light-harvesting proteins. While the individual characteristics of these chlorophylls are well understood, the advantages of their coexistence remain unclear. In this study, we establish a method to simulate excitation energy transfer within the entire photosystem II supercomplex by using network analysis integrated with quantum dynamic calculations. We then investigate the effects of the coexistence of chlorophyll a and chlorophyll b by comparing various chlorophyll compositions. Our results reveal that the natural chlorophyll composition allows the excited energy to preferentially flow through specific domains that act as safety valves, preventing downstream overflow. Our findings suggest that the light-harvesting proteins in a photosystem II supercomplex achieve evolutionary advantages with the natural chlorophyll a/b ratio, capturing light energy efficiently and safely across various light intensities. Using our framework, one can better understand how green plants harvest light energy and adapt to changing environmental conditions.
在绿色植物中，叶绿素a和叶绿素b是与光捕获蛋白结合的主要色素。虽然这些叶绿素的个体特性已得到充分了解，但其共存的优势仍不明确。在本研究中，我们建立了一种方法，通过结合量子动力学计算的网络分析来模拟整个光系统II超复合物内的激发能转移。然后，我们通过比较各种叶绿素组成来研究叶绿素a和叶绿素b共存的影响。我们的结果表明，天然叶绿素组成使激发能优先通过充当安全阀的特定区域流动，防止下游能量溢出。我们的研究结果表明，光系统II超复合物中的光捕获蛋白以天然叶绿素a/b比例获得进化优势，能够在各种光强下高效且安全地捕获光能。使用我们的框架，可以更好地理解绿色植物如何捕获光能并适应不断变化的环境条件。
