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Publication Abstract from PubMed

Photosystem I (PSI) is a highly efficient natural light-energy converter, and has diverse light-harvesting antennas associated with its core in different photosynthetic organisms. In green algae, an extremely large light-harvesting complex I (LHCI) captures and transfers energy to the PSI core. Here, we report the structure of PSI-LHCI from a green alga Bryopsis corticulans at 3.49 A resolution, obtained by single-particle cryo-electron microscopy, which revealed 13 core subunits including subunits characteristic of both prokaryotes and eukaryotes, and 10 light-harvesting complex a (Lhca) antennas that form a double semi-ring and an additional Lhca dimer, including a novel four-transmembrane-helix Lhca. In total, 244 chlorophylls were identified, some of which were located at key positions for the fast energy transfer. These results provide a firm structural basis for unravelling the mechanisms of light-energy harvesting, transfer and quenching in the green algal PSI-LHCI, and important clues as to how PSI-LHCI has changed during evolution.

Structure of a green algal photosystem I in complex with a large number of light-harvesting complex I subunits.,Qin X, Pi X, Wang W, Han G, Zhu L, Liu M, Cheng L, Shen JR, Kuang T, Sui SF Nat Plants. 2019 Mar;5(3):263-272. doi: 10.1038/s41477-019-0379-y. Epub 2019 Mar , 8. PMID:30850820^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.