Crystal Structure of dodecameric FMN-dependent Ubix-like Decarboxylase from Escherichia coli O157:H7

Experimental Data Snapshot

  • Resolution: 2.00 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.180 

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Crystal structure of a dodecameric FMN-dependent UbiX-like decarboxylase (Pad1) from Escherichia coli O157: H7.

Rangarajan, E.S.Li, Y.Iannuzzi, P.Tocilj, A.Hung, L.-W.Matte, A.Cygler, M.

(2004) Protein Sci 13: 3006-3016

  • DOI: https://doi.org/10.1110/ps.04953004
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    The crystal structure of the flavoprotein Pad1 from Escherichia coli O157:H7 complexed with the cofactor FMN has been determined by the multiple anomalous diffraction method and refined at 2.0 A resolution. This protein is a paralog of UbiX (3-octaprenyl-4-hydroxybenzoate carboxylyase, 51% sequence identity) that catalyzes the third step in ubiquinone biosynthesis and to Saccharomyces cerevisiae Pad1 (54% identity), an enzyme that confers resistance to the antimicrobial compounds phenylacrylic acids through decarboxylation of these compounds. Each Pad1 monomer consists of a typical Rossmann fold containing a non-covalently bound molecule of FMN. The fold of Pad1 is similar to MrsD, an enzyme associated with lantibiotic synthesis; EpiD, a peptidyl-cysteine decarboxylase; and AtHAL3a, the enzyme, which decarboxylates 4'-phosphopantothenoylcysteine to 4'-phosphopantetheine during coenzyme A biosynthesis, all with a similar location of the FMN binding site at the interface between two monomers, yet each having little sequence similarity to one another. All of these proteins associate into oligomers, with a trimer forming the common structural unit in each case. In MrsD and EpiD, which belong to the homo-dodecameric flavin-containing cysteine decarboxylase (HFCD) family, these trimers associate further into dodecamers. Pad1 also forms dodecamers, although the association of the trimers is completely different, resulting in exposure of a different side of the trimer unit to the solvent. This exposure affects the location of the substrate binding site and, specifically, its access to the FMN cofactor. Therefore, Pad1 forms a separate family, distinguishable from the HFCD family.

  • Organizational Affiliation

    Biotechnology Research Institute, NRCC, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2, Canada.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Probable aromatic acid decarboxylase
A, B, C, D
197Escherichia coli O157:H7Mutation(s): 11 
Gene Names: pad1Z4047ECs3593ecdB
EC: 4.1.1 (PDB Primary Data), (UniProt)
Find proteins for P69772 (Escherichia coli O157:H7)
Explore P69772 
Go to UniProtKB:  P69772
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP69772
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.00 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.176 
  • R-Value Observed: 0.180 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 95.372α = 90
b = 95.372β = 90
c = 217.538γ = 120
Software Package:
Software NamePurpose
HKL-2000data reduction
SCALEPACKdata scaling

Structure Validation

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Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2004-10-26
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Source and taxonomy, Version format compliance
  • Version 1.3: 2018-01-31
    Changes: Experimental preparation
  • Version 1.4: 2019-07-24
    Changes: Data collection, Derived calculations, Refinement description