8HG3
Cryo-EM structure of the Lhcp complex from Ostreococcus tauri
Summary for 8HG3
| Entry DOI | 10.2210/pdb8hg3/pdb |
| EMDB information | 34733 |
| Descriptor | Chlorophyll a-b binding protein, chloroplastic, CHLOROPHYLL A, CHLOROPHYLL B, ... (7 entities in total) |
| Functional Keywords | complex, light-harvesting, electron transport, photosynthesis |
| Biological source | Ostreococcus tauri |
| Total number of polymer chains | 3 |
| Total formula weight | 122609.62 |
| Authors | Shan, J.,Sheng, X.,Ishii, A.,Watanabe, A.,Song, C.,Murata, K.,Minagawa, J.,Liu, Z. (deposition date: 2022-11-13, release date: 2023-04-26) |
| Primary citation | Ishii, A.,Shan, J.,Sheng, X.,Kim, E.,Watanabe, A.,Yokono, M.,Noda, C.,Song, C.,Murata, K.,Liu, Z.,Minagawa, J. The photosystem I supercomplex from a primordial green alga Ostreococcus tauri harbors three light-harvesting complex trimers. Elife, 12:-, 2023 Cited by PubMed Abstract: As a ubiquitous picophytoplankton in the ocean and an early-branching green alga, is a model prasinophyte species for studying the functional evolution of the light-harvesting systems in photosynthesis. Here, we report the structure and function of the photosystem I (PSI) supercomplex in low light conditions, where it expands its photon-absorbing capacity by assembling with the light-harvesting complexes I (LHCI) and a prasinophyte-specific light-harvesting complex (Lhcp). The architecture of the supercomplex exhibits hybrid features of the plant-type and the green algal-type PSI supercomplexes, consisting of a PSI core, an Lhca1-Lhca4-Lhca2-Lhca3 belt attached on one side and an Lhca5-Lhca6 heterodimer associated on the other side between PsaG and PsaH. Interestingly, nine Lhcp subunits, including one Lhcp1 monomer with a phosphorylated amino-terminal threonine and eight Lhcp2 monomers, oligomerize into three trimers and associate with PSI on the third side between Lhca6 and PsaK. The Lhcp1 phosphorylation and the light-harvesting capacity of PSI were subjected to reversible photoacclimation, suggesting that the formation of PSI-LHCI-Lhcp supercomplex is likely due to a phosphorylation-dependent mechanism induced by changes in light intensity. Notably, this supercomplex did not exhibit far-red peaks in the 77 K fluorescence spectra, which is possibly due to the weak coupling of the chlorophyll 603-609 pair in Lhca1-4. PubMed: 36951548DOI: 10.7554/eLife.84488 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (2.94 Å) |
Structure validation
Download full validation report
