Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 9.40 kDa 
• Atom Count: 614 
• Modelled Residue Count: 80 
• Deposited Residue Count: 80 
• Unique protein chains: 1

1K0T

NMR SOLUTION STRUCTURE OF UNBOUND, OXIDIZED PHOTOSYSTEM I SUBUNIT PSAC, CONTAINING [4FE-4S] CLUSTERS FA AND FB

• PDB DOI: 10.2210/pdb1K0T/pdb

• Classification: ELECTRON TRANSPORT
• Organism(s): Synechococcus sp. PCC 7002
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2001-09-20 Released: 2002-06-05 
• Deposition Author(s): Antonkine, M.L., Liu, G., Bentrop, D., Bryant, D.A., Bertini, I., Luchinat, C., Golbeck, J.H., Stehlik, D.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 400 
• Conformers Submitted: 30 
• Selection Criteria: LEAST RESTRAINT VIOLATIONS 

Literature

Solution structure of the unbound, oxidized Photosystem I subunit PsaC, containing [4Fe-4S] clusters F(A) and F(B): a conformational change occurs upon binding to photosystem I.

Antonkine, M.L., Liu, G., Bentrop, D., Bryant, D.A., Bertini, I., Luchinat, C., Golbeck, J.H., Stehlik, D.

(2002) J Biol Inorg Chem 7: 461-472

• PubMed: 11941504 
• DOI: 10.1007/s00775-001-0321-3
• Primary Citation of Related Structures:  
  1K0T


• PubMed Abstract: 
  

This work presents the three-dimensional NMR solution structure of recombinant, oxidized, unbound PsaC from Synechococcus sp. PCC 7002. Constraints are derived from homo- and heteronuclear one-, two- and three-dimensional (1)H and (15)N NMR data. Significant differences are outlined between the unbound PsaC structure presented here and the available X-ray structure of bound PsaC as an integral part of the whole cyanobacterial PS I complex. These differences mainly concern the arrangement of the N- and C-termini with respect to the [4Fe-4S] core domain. In the NMR solution structure of PsaC the C-terminal region assumes a disordered helical conformation, and is clearly different from the extended coil conformation, which is one of the structural elements required to anchor PsaC to the PS I core heterodimer. In solution the N-terminus of PsaC is in contact with the pre-C-terminal region but slides in between the latter and the iron-sulfur core region of the protein. Together, these features result in a concerted movement of the N-terminus and pre-C-terminal region away from the F(A) binding site, accompanied by a bending of the N-terminus. In comparison, the same terminal regions are positioned much closer to F(A) and take up an anti-parallel beta-sheet arrangement in PsaC bound to PS I. The conformational changes between bound and unbound PsaC correlate with the differences reported earlier for the EPR spectra of reduced F(A) and F(B) in bound versus unbound PsaC. The observed different structural features in solution are highly relevant for unraveling the stepwise assembly process of the stromal PsaC, PsaD and PsaE subunits to the PS I core heterodimer. Electronic supplementary material to this paper can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00775-001-0321-3.

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Organizational Affiliation: 

Present address: Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PSAC SUBUNIT OF PHOTOSYSTEM I	A	80	Synechococcus sp. PCC 7002	Mutation(s): 0  Gene Names: psaC, SYNPCC7002_A1589 EC: 1.97.1.12
UniProt
Find proteins for P31087 (Synechococcus sp. (strain ATCC 27264 / PCC 7002 / PR-6)) Explore P31087  Go to UniProtKB:  P31087

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SF4	B [auth A], C [auth A]	IRON/SULFUR CLUSTER Fe4 S4 LJBDFODJNLIPKO-VKOJMFJBAC

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 400 
• Conformers Submitted: 30 
• Selection Criteria: LEAST RESTRAINT VIOLATIONS 
• OLDERADO: 1K0T Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-09-20 
• Released Date: 2002-06-05 
Deposition Author(s): Antonkine, M.L., Liu, G., Bentrop, D., Bryant, D.A., Bertini, I., Luchinat, C., Golbeck, J.H., Stehlik, D.

Revision History  

• Version 1.0: 2002-06-05
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Source and taxonomy, Version format compliance