8WGH

Cryo-EM structure of the red-shifted Fittonia albivenis PSI-LHCI

Summary for 8WGH

• Entry DOI: 10.2210/pdb8wgh/pdb
• EMDB information: 37513
• Descriptor: Chlorophyll a-b binding protein 1, Photosystem I reaction center subunit III, chloroplastic, Photosystem I reaction center subunit VIII, ... (30 entities in total)
• Functional Keywords: complex, photosynthesis
• Biological source: Fittonia albivenis; More
• Total number of polymer chains: 18
• Total formula weight: 637515.15

Authors

Huang, G.Q.,Li, X.X.,Sui, S.F.,Qin, X.C. (deposition date: 2023-09-21, release date: 2024-07-10, Last modification date: 2025-07-23)

Primary citation

Li, X.,Huang, G.,Zhu, L.,Hao, C.,Sui, S.F.,Qin, X.
Structure of the red-shifted Fittonia albivenis photosystem I.
Nat Commun, 15:6325-6325, 2024

PubMed Abstract: Photosystem I (PSI) from Fittonia albivenis, an Acanthaceae ornamental plant, is notable among green plants for its red-shifted emission spectrum. Here, we solved the structure of a PSI-light harvesting complex I (LHCI) supercomplex from F. albivenis at 2.46-Å resolution using cryo-electron microscopy. The supercomplex contains a core complex of 14 subunits and an LHCI belt with four antenna subunits (Lhca1-4) similar to previously reported angiosperm PSI-LHCI structures; however, Lhca3 differs in three regions surrounding a dimer of low-energy chlorophylls (Chls) termed red Chls, which absorb far-red beyond visible light. The unique amino acid sequences within these regions are exclusively shared by plants with strongly red-shifted fluorescence emission, suggesting candidate structural elements for regulating the energy state of red Chls. These results provide a structural basis for unraveling the mechanisms of light harvest and transfer in PSI-LHCI of under canopy plants and for designing Lhc to harness longer-wavelength light in the far-red spectral range.

PubMed: 39060282
DOI: 10.1038/s41467-024-50655-9

Experimental method

ELECTRON MICROSCOPY (2.4 Å)