1KEK

Crystal Structure of the Free Radical Intermediate of Pyruvate:Ferredoxin Oxidoreductase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.178 
  • R-Value Observed: 0.178 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of the free radical intermediate of pyruvate:ferredoxin oxidoreductase.

Chabriere, E.Vernede, X.Guigliarelli, B.Charon, M.H.Hatchikian, E.C.Fontecilla-Camps, J.C.

(2001) Science 294: 2559-2563

  • DOI: 10.1126/science.1066198
  • Primary Citation of Related Structures:  
    1KEK

  • PubMed Abstract: 
  • In anaerobic organisms, the decarboxylation of pyruvate, a crucial component of intermediary metabolism, is catalyzed by the metalloenzyme pyruvate: ferredoxin oxidoreductase (PFOR) resulting in the generation of low potential electrons and the subse ...

    In anaerobic organisms, the decarboxylation of pyruvate, a crucial component of intermediary metabolism, is catalyzed by the metalloenzyme pyruvate: ferredoxin oxidoreductase (PFOR) resulting in the generation of low potential electrons and the subsequent acetylation of coenzyme A (CoA). PFOR is the only enzyme for which a stable acetyl thiamine diphosphate (ThDP)-based free radical reaction intermediate has been identified. The 1.87 A-resolution structure of the radical form of PFOR from Desulfovibrio africanus shows that, despite currently accepted ideas, the thiazole ring of the ThDP cofactor is markedly bent, indicating a drastic reduction of its aromaticity. In addition, the bond connecting the acetyl group to ThDP is unusually long, probably of the one-electron type already described for several cation radicals but not yet found in a biological system. Taken together, our data, along with evidence from the literature, suggest that acetyl-CoA synthesis by PFOR proceeds via a condensation mechanism involving acetyl (PFOR-based) and thiyl (CoA-based) radicals.


    Organizational Affiliation

    Laboratoire de Cristallographie et Cristallogenèse des Protéines, Institut de Biologie Structurale Jean-Pierre Ebel, Commissariat à l'Energie Atomique, Université Joseph Fourier, CNRS, 41, rue Jules Horowitz, 38027 Grenoble Cedex 1, France.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Pyruvate-Ferredoxin OxidoreductaseAB1231Desulfocurvibacter africanusMutation(s): 0 
Gene Names: por
EC: 1.2.7.1
Find proteins for P94692 (Desulfocurvibacter africanus)
Explore P94692 
Go to UniProtKB:  P94692
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 5 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HTL
Query on HTL

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A, B
2-ACETYL-THIAMINE DIPHOSPHATE
C14 H21 N4 O8 P2 S
GYRGKLZCJRVYRV-UHFFFAOYSA-O
 Ligand Interaction
SF4
Query on SF4

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A, B
IRON/SULFUR CLUSTER
Fe4 S4
LJBDFODJNLIPKO-VKOJMFJBAC
 Ligand Interaction
CO2
Query on CO2

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A, B
CARBON DIOXIDE
C O2
CURLTUGMZLYLDI-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

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A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
MG
Query on MG

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A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.178 
  • R-Value Observed: 0.178 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 86.11α = 90
b = 145.76β = 90
c = 210.26γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling
X-PLORmodel building
X-PLORrefinement
REFMACrefinement
CCP4data scaling
X-PLORphasing

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-12-21
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance