9V7U

PSI-LHCE supercomplex from Euglena gracilis.

Summary for 9V7U

• Entry DOI: 10.2210/pdb9v7u/pdb
• EMDB information: 64824
• Descriptor: Photosystem I P700 chlorophyll a apoprotein A1, Chloroplast light-harvesting complex I protein, LHCE 3, ... (35 entities in total)
• Functional Keywords: psi-elhci, euglena gracilis., photosynthesis
• Biological source: Euglena gracilis; More
• Total number of polymer chains: 24
• Total formula weight: 842538.47

Authors

Bai, T.Y.,Mao, Z.Y.,Tian, L.R. (deposition date: 2025-05-28, release date: 2026-04-01)

Primary citation

Bai, T.,Mao, Z.,Sun, D.,Tang, Y.,Lu, Z.,Ma, F.,Ma, B.,Chen, J.,Wang, W.,Li, Y.,Liu, S.,Yang, Y.,Wang, Y.,Tian, L.
Structural basis of diadinoxanthin-Chl a/b-binding proteins in the photosystem I supercomplex of Euglena gracilis.
Sci Adv, 12:eaea5561-eaea5561, 2026

PubMed Abstract: is a phototrophic flagellate that has evolved through secondary endosymbiotic events and belongs to green-lineage organisms. We report a unique structure of photosystem I-light harvesting complex I (PSI-LHCI) supercomplex from at a 2.23-angstrom resolution by cryo-electron microscopy. The supercomplex is composed of 8 core subunits and 16 LHCIs and exhibits distinctive structural features compared to its counterparts in green algae and plants. The LHCI subunits encircle the core complex, forming a two-layered arrangement that comprises six pairs of tightly packed heterodimers. Specifically, the 16 LHCIs consist of 4 diadinoxanthin-chlorophyll (Chl) a/b-binding antennae (Lhcbm) and 12 diadinoxanthin-Chl a-binding antennae (Lhca), and they exhibit characteristic pigment compositions combining features of green- and red-lineage organisms. These findings provide a robust structural foundation for elucidating the mechanisms of light harvesting and energy transfer as well as insights into the evolutionary changes of green-lineage PSI-LHCI.

PubMed: 41790873
DOI: 10.1126/sciadv.aea5561

Experimental method

ELECTRON MICROSCOPY (2.63 Å)