8IWH

Structure and characteristics of a photosystem II supercomplex containing monomeric LHCX and dimeric FCPII antennae from the diatom Thalassiosira pseudonana

Summary for 8IWH

• Entry DOI: 10.2210/pdb8iwh/pdb
• EMDB information: 35766
• Descriptor: Photosystem II protein D1, Photosystem II reaction center protein J, Photosystem II reaction center protein K, ... (48 entities in total)
• Functional Keywords: psii supercomplex, lhcx, fcp, photosynthesis
• Biological source: Thalassiosira pseudonana (Marine diatom, Cyclotella nana); More
• Total number of polymer chains: 56
• Total formula weight: 1220689.95

Authors

Feng, Y.,Li, Z.H.,Wang, W.D.,Shen, J.R. (deposition date: 2023-03-30, release date: 2023-10-25, Last modification date: 2023-11-08)

Primary citation

Feng, Y.,Li, Z.,Li, X.,Shen, L.,Liu, X.,Zhou, C.,Zhang, J.,Sang, M.,Han, G.,Yang, W.,Kuang, T.,Wang, W.,Shen, J.R.
Structure of a diatom photosystem II supercomplex containing a member of Lhcx family and dimeric FCPII.
Sci Adv, 9:eadi8446-eadi8446, 2023

PubMed Abstract: Diatoms rely on fucoxanthin chlorophyll -binding proteins (FCPs) for their great success in oceans, which have a great diversity in their pigment, protein compositions, and subunit organizations. We report a unique structure of photosystem II (PSII)-FCPII supercomplex from at 2.68-Å resolution by cryo-electron microscopy. FCPIIs within this PSII-FCPII supercomplex exist in dimers and monomers, and a homodimer and a heterodimer were found to bind to a PSII core. The FCPII homodimer is formed by Lhcf7 and associates with PSII through an Lhcx family antenna Lhcx6_1, whereas the heterodimer is formed by Lhcf6 and Lhcf11 and connects to the core together with an Lhcf5 monomer through Lhca2 monomer. An extended pigment network consisting of diatoxanthins, diadinoxanthins, fucoxanthins, and chlorophylls is revealed, which functions in efficient light harvesting, energy transfer, and dissipation. These results provide a structural basis for revealing the energy transfer and dissipation mechanisms and also for the structural diversity of FCP antennas in diatoms.

PubMed: 37878698
DOI: 10.1126/sciadv.adi8446

Experimental method

ELECTRON MICROSCOPY (2.68 Å)