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Open data
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Basic information
Entry | Database: PDB / ID: 7zqe | |||||||||||||||
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Title | Plastocyanin bound to PSI of Chlamydomonas reinhardtii | |||||||||||||||
![]() | Plastocyanin, chloroplastic | |||||||||||||||
![]() | PHOTOSYNTHESIS / green algae / dimeric PSI | |||||||||||||||
Function / homology | ![]() electron transporter, transferring electrons from cytochrome b6/f complex of photosystem II activity / chloroplast thylakoid lumen / chloroplast thylakoid membrane / copper ion binding Similarity search - Function | |||||||||||||||
Biological species | ![]() ![]() | |||||||||||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 2.55 Å | |||||||||||||||
![]() | Naschberger, A. / Amunts, A. | |||||||||||||||
Funding support | ![]() ![]()
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![]() | ![]() Title: Algal photosystem I dimer and high-resolution model of PSI-plastocyanin complex. Authors: Andreas Naschberger / Laura Mosebach / Victor Tobiasson / Sebastian Kuhlgert / Martin Scholz / Annemarie Perez-Boerema / Thi Thu Hoai Ho / André Vidal-Meireles / Yuichiro Takahashi / ...Authors: Andreas Naschberger / Laura Mosebach / Victor Tobiasson / Sebastian Kuhlgert / Martin Scholz / Annemarie Perez-Boerema / Thi Thu Hoai Ho / André Vidal-Meireles / Yuichiro Takahashi / Michael Hippler / Alexey Amunts / ![]() ![]() ![]() ![]() Abstract: Photosystem I (PSI) enables photo-electron transfer and regulates photosynthesis in the bioenergetic membranes of cyanobacteria and chloroplasts. Being a multi-subunit complex, its macromolecular ...Photosystem I (PSI) enables photo-electron transfer and regulates photosynthesis in the bioenergetic membranes of cyanobacteria and chloroplasts. Being a multi-subunit complex, its macromolecular organization affects the dynamics of photosynthetic membranes. Here we reveal a chloroplast PSI from the green alga Chlamydomonas reinhardtii that is organized as a homodimer, comprising 40 protein subunits with 118 transmembrane helices that provide scaffold for 568 pigments. Cryogenic electron microscopy identified that the absence of PsaH and Lhca2 gives rise to a head-to-head relative orientation of the PSI-light-harvesting complex I monomers in a way that is essentially different from the oligomer formation in cyanobacteria. The light-harvesting protein Lhca9 is the key element for mediating this dimerization. The interface between the monomers is lacking PsaH and thus partially overlaps with the surface area that would bind one of the light-harvesting complex II complexes in state transitions. We also define the most accurate available PSI-light-harvesting complex I model at 2.3 Å resolution, including a flexibly bound electron donor plastocyanin, and assign correct identities and orientations to all the pigments, as well as 621 water molecules that affect energy transfer pathways. | |||||||||||||||
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Structure visualization
Structure viewer | Molecule: ![]() ![]() |
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Downloads & links
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Download
PDBx/mmCIF format | ![]() | 38.9 KB | Display | ![]() |
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PDB format | ![]() | 28 KB | Display | ![]() |
PDBx/mmJSON format | ![]() | Tree view | ![]() | |
Others | ![]() |
-Validation report
Summary document | ![]() | 618.7 KB | Display | ![]() |
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Full document | ![]() | 618.4 KB | Display | |
Data in XML | ![]() | 21.3 KB | Display | |
Data in CIF | ![]() | 29.6 KB | Display | |
Arichive directory | ![]() ![]() | HTTPS FTP |
-Related structure data
Related structure data | ![]() 14872MC ![]() 7zq9C ![]() 7zqcC ![]() 7zqdC M: map data used to model this data C: citing same article ( |
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Similar structure data | Similarity search - Function & homology ![]() |
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Links
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Assembly
Deposited unit | ![]()
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1 |
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Components
#1: Protein | Mass: 14889.784 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) ![]() ![]() |
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#2: Chemical | ChemComp-CU / |
Has ligand of interest | Y |
-Experimental details
-Experiment
Experiment | Method: ELECTRON MICROSCOPY |
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EM experiment | Aggregation state: PARTICLE / 3D reconstruction method: single particle reconstruction |
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Sample preparation
Component | Name: Photosystem I dimer of Chlamydomonas reinhardtii / Type: ORGANELLE OR CELLULAR COMPONENT / Entity ID: #1 / Source: NATURAL |
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Molecular weight | Value: 0.7 MDa / Experimental value: YES |
Source (natural) | Organism: ![]() ![]() |
Buffer solution | pH: 7.5 |
Specimen | Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES |
Vitrification | Cryogen name: ETHANE |
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Electron microscopy imaging
Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |
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Microscopy | Model: FEI TITAN KRIOS |
Electron gun | Electron source: ![]() |
Electron lens | Mode: BRIGHT FIELD / Nominal defocus max: 5000 nm / Nominal defocus min: 1000 nm |
Image recording | Electron dose: 45.8 e/Å2 / Film or detector model: GATAN K3 BIOQUANTUM (6k x 4k) |
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Processing
CTF correction | Type: PHASE FLIPPING ONLY |
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3D reconstruction | Resolution: 2.55 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 66080 / Symmetry type: POINT |