Green plants capture light that spans the visible solar spectrum. A broad spectral range is required for sufficient absorption, which means that energy must be funneled rapidly and efficiently downhill to drive charge separation and water splitting. Carotenoids, the accessory pigments in photosynthesis, play light harvesting, photoprotective, and structural roles. Understanding these roles is challenging because their energetics are highly sensitive to their environment. In this work, we discover that a single carotenoid in the major antenna complex of green plants (LHCII) serves as the nexus of light harvesting by accumulating energy and transferring it through a debated dark state. These photophysics reveal how plants expand their capacity to capture and utilize solar energy.
Son, M., Pinnola, A., Bassi, R., & Schlau-Cohen, G. S. (2019). The Electronic Structure of Lutein 2 Is Optimized for Light Harvesting in Plants. Chem, 5(3), 575–584. https://doi.org/10.1016/j.chempr.2018.12.016