6KIF
Structure of cyanobacterial photosystem I-IsiA-flavodoxin supercomplex
This is a non-PDB format compatible entry.
Summary for 6KIF
| Entry DOI | 10.2210/pdb6kif/pdb |
| EMDB information | 9994 |
| Descriptor | Photosystem I P700 chlorophyll a apoprotein A1, Photosystem I reaction center subunit XI, PsaM, ... (23 entities in total) |
| Functional Keywords | photosystem, antenna, chlorophyll-binding protein, membrane protein, photosynthesis, iron stress-induced protein a, flavodoxin |
| Biological source | Synechococcus elongatus (strain PCC 7942) More |
| Total number of polymer chains | 54 |
| Total formula weight | 2159108.06 |
| Authors | Cao, P.,Cao, D.F.,Si, L.,Su, X.D.,Chang, W.R.,Liu, Z.F.,Zhang, X.Z.,Li, M. (deposition date: 2019-07-18, release date: 2020-02-12, Last modification date: 2024-10-23) |
| Primary citation | Cao, P.,Cao, D.,Si, L.,Su, X.,Tian, L.,Chang, W.,Liu, Z.,Zhang, X.,Li, M. Structural basis for energy and electron transfer of the photosystem I-IsiA-flavodoxin supercomplex. Nat.Plants, 6:167-176, 2020 Cited by PubMed Abstract: Under iron-deficiency stress, which occurs frequently in natural aquatic environments, cyanobacteria reduce the amount of iron-enriched proteins, including photosystem I (PSI) and ferredoxin (Fd), and upregulate the expression of iron-stress-induced proteins A and B (IsiA and flavodoxin (Fld)). Multiple IsiAs function as the peripheral antennae that encircle the PSI core, whereas Fld replaces Fd as the electron receptor of PSI. Here, we report the structures of the PSI-IsiA-Fld and PSI-IsiA supercomplexes from Synechococcus sp. PCC 7942, revealing features that are different from the previously reported PSI structures, and a sophisticated pigment network that involves previously unobserved pigment molecules. Spectroscopic results demonstrated that IsiAs are efficient light harvesters for PSI. Three Flds bind symmetrically to the trimeric PSI core-we reveal the detailed interaction and the electron transport path between PSI and Fld. Our results provide a structural basis for understanding the mechanisms of light harvesting, energy transfer and electron transport of cyanobacterial PSI under stressed conditions. PubMed: 32042157DOI: 10.1038/s41477-020-0593-7 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.3 Å) |
Structure validation
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