2PUK

Crystal structure of the binary complex between ferredoxin: thioredoxin reductase and thioredoxin m


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.284 
  • R-Value Work: 0.235 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structural snapshots along the reaction pathway of ferredoxin-thioredoxin reductase.

Dai, S.Friemann, R.Glauser, D.A.Bourquin, F.Manieri, W.Schurmann, P.Eklund, H.

(2007) Nature 448: 92-96

  • DOI: 10.1038/nature05937
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Oxygen-evolving photosynthetic organisms regulate carbon metabolism through a light-dependent redox signalling pathway. Electrons are shuttled from photosystem I by means of ferredoxin (Fdx) to ferredoxin-thioredoxin reductase (FTR), which catalyses ...

    Oxygen-evolving photosynthetic organisms regulate carbon metabolism through a light-dependent redox signalling pathway. Electrons are shuttled from photosystem I by means of ferredoxin (Fdx) to ferredoxin-thioredoxin reductase (FTR), which catalyses the two-electron-reduction of chloroplast thioredoxins (Trxs). These modify target enzyme activities by reduction, regulating carbon flow. FTR is unique in its use of a [4Fe-4S] cluster and a proximal disulphide bridge in the conversion of a light signal into a thiol signal. We determined the structures of FTR in both its one- and its two-electron-reduced intermediate states and of four complexes in the pathway, including the ternary Fdx-FTR-Trx complex. Here we show that, in the first complex (Fdx-FTR) of the pathway, the Fdx [2Fe-2S] cluster is positioned suitably for electron transfer to the FTR [4Fe-4S] centre. After the transfer of one electron, an intermediate is formed in which one sulphur atom of the FTR active site is free to attack a disulphide bridge in Trx and the other sulphur atom forms a fifth ligand for an iron atom in the FTR [4Fe-4S] centre--a unique structure in biology. Fdx then delivers a second electron that cleaves the FTR-Trx heterodisulphide bond, which occurs in the Fdx-FTR-Trx complex. In this structure, the redox centres of the three proteins are aligned to maximize the efficiency of electron transfer from the Fdx [2Fe-2S] cluster to the active-site disulphide of Trxs. These results provide a structural framework for understanding the mechanism of disulphide reduction by an iron-sulphur enzyme and describe previously unknown interaction networks for both Fdx and Trx (refs 4-6).


    Organizational Affiliation

    Howard Hughes Medical Institute, Integrated Department of Immunology, National Jewish Medical and Research Center & University of Colorado Health Sciences Center, 1400 Jackson Street, Denver, Colorado 80206, USA. dais@njc.org




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ferredoxin-thioredoxin reductase, catalytic chain
A, E
109Synechocystis sp. (strain PCC 6803 / Kazusa)Mutation(s): 0 
Gene Names: ftrC
EC: 1.8.7.2
Find proteins for Q55389 (Synechocystis sp. (strain PCC 6803 / Kazusa))
Go to UniProtKB:  Q55389
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Ferredoxin-thioredoxin reductase, variable chain
B, F
73Synechocystis sp. (strain PCC 6803 / Kazusa)Mutation(s): 0 
Gene Names: ftrV
Find proteins for Q55781 (Synechocystis sp. (strain PCC 6803 / Kazusa))
Go to UniProtKB:  Q55781
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Thioredoxin M-type, chloroplast (TRX-M)
C, G
106Spinacia oleraceaMutation(s): 1 
Find proteins for P07591 (Spinacia oleracea)
Go to UniProtKB:  P07591
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SF4
Query on SF4

Download SDF File 
Download CCD File 
A, E
IRON/SULFUR CLUSTER
Fe4 S4
LJBDFODJNLIPKO-VKOJMFJBAC
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.284 
  • R-Value Work: 0.235 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 53.952α = 90.00
b = 42.223β = 90.29
c = 145.344γ = 90.00
Software Package:
Software NamePurpose
ADSCdata collection
MOLREPphasing
MOSFLMdata reduction
PDB_EXTRACTdata extraction
SCALAdata scaling
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-07-10
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2013-09-18
    Type: Derived calculations