Crystal Structure of 4-Hydroxybutyryl-CoA Dehydratase from Clostridium aminobutyricum: Radical catalysis involving a [4Fe-4S] cluster and flavin

Experimental Data Snapshot

  • Resolution: 1.60 Å
  • R-Value Free: 0.212 
  • R-Value Work: 0.163 
  • R-Value Observed: 0.165 

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Crystal structure of 4-hydroxybutyryl-CoA dehydratase: radical catalysis involving a [4Fe-4S] cluster and flavin.

Martins, B.M.Dobbek, H.Cinkaya, I.Buckel, W.Messerschmidt, A.

(2004) Proc Natl Acad Sci U S A 101: 15645-15649

  • DOI: https://doi.org/10.1073/pnas.0403952101
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Dehydratases catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the elimination of water. The 1.6-A resolution crystal structure of 4-hydroxybutyryl-CoA dehydratase from the gamma-aminobutyrate-fermenting Clostridium aminobutyricum represents a new class of dehydratases with an unprecedented active site architecture. A [4Fe-4S](2+) cluster, coordinated by three cysteine and one histidine residues, is located 7 A from the Re-side of a flavin adenine dinucleotide (FAD) moiety. The structure provides insight into the function of these ubiquitous prosthetic groups in the chemically nonfacile, radical-mediated dehydration of 4-hydroxybutyryl-CoA. The substrate can be bound between the [4Fe-4S](2+) cluster and the FAD with both cofactors contributing to its radical activation and catalytic conversion. Our results raise interesting questions regarding the mechanism of acyl-CoA dehydrogenases, which are involved in fatty acid oxidation, and address the divergent evolution of the ancestral common gene.

  • Organizational Affiliation

    Max-Planck-Institut Biochemie, Strukturforschung, 82152 Martinsried, Germany. martins@biochem.mpg.de

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Gamma-aminobutyrate metabolism dehydratase/isomerase
A, B, C, D
490Clostridium aminobutyricumMutation(s): 0 
EC: 4.2 (PDB Primary Data), (PDB Primary Data)
Find proteins for P55792 (Clostridium aminobutyricum)
Explore P55792 
Go to UniProtKB:  P55792
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP55792
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.60 Å
  • R-Value Free: 0.212 
  • R-Value Work: 0.163 
  • R-Value Observed: 0.165 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 102.3α = 90
b = 130.2β = 90
c = 175.5γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
XDSdata scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-12-21
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-10-11
    Changes: Advisory, Refinement description
  • Version 1.4: 2019-07-24
    Changes: Data collection, Refinement description
  • Version 1.5: 2024-02-14
    Changes: Advisory, Data collection, Database references, Derived calculations