Download MendeleyStructural basis for energy harvesting and dissipation in a diatom PSII-FCPII supercomplex.
Nagao, R., Kato, K., Suzuki, T., Ifuku, K., Uchiyama, I., Kashino, Y., Dohmae, N., Akimoto, S., Shen, J.R., Miyazaki, N., Akita, F.(2019) Nat Plants 5: 890-901
- PubMed: 31358960
- DOI: https://doi.org/10.1038/s41477-019-0477-x
- Primary Citation of Related Structures:
6J3Y, 6J3Z, 6J40 - PubMed Abstract:
Light-harvesting antenna systems in photosynthetic organisms harvest solar energy and transfer it to the photosynthetic reaction centres to initiate charge-separation and electron-transfer reactions. Diatoms are one of the important groups of oxyphototrophs and possess fucoxanthin chlorophyll a/c-binding proteins (FCPs) as light harvesters. The organization and association pattern of FCP with the photosystem II (PSII) core are unknown. Here we solved the structure of PSII-FCPII supercomplexes isolated from a diatom, Chaetoceros gracilis, by single-particle cryoelectron microscopy. The PSII-FCPII forms a homodimer. In each monomer, two FCP homotetramers and three FCP monomers are associated with one PSII core. The structure reveals a highly complicated protein-pigment network that is different from the green-type light-harvesting apparatus. Comparing these two systems allows the identification of energy transfer and quenching pathways. These findings provide structural insights into not only excitation-energy transfer mechanisms in the diatom PSII-FCPII, but also changes of light harvesters between the red- and green-lineage oxyphototrophs during evolution.
Organizational Affiliation:
Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan.
