Structure of a green algal photosystem I in complex with a large number of light-harvesting complex I subunits

作  者:Qin XC, Pi X, Wang WD, Hang GY, Zhu LX, Liu MM, Cheng LP, Shen JR, Kuang TY*, Sui SF*
影响因子:13.297
刊物名称:Nature Plants
出版年份:2019
卷:5  期:3  页码:263-272

论文摘要:

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 angstorm 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.

全文链接:https://www.nature.com/articles/s41477-019-0379-y