2JL4

Holo structure of Maleyl Pyruvate Isomerase, a bacterial glutathione- s-transferase in Zeta class


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.211 
  • R-Value Observed: 0.214 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structure of Bacterial Glutathione-S-Transferase Maleyl Pyruvate Isomerase and Implications for Mechanism of Isomerisation.

Marsh, M.Shoemark, D.K.Jacob, A.Robinson, C.Cahill, B.Zhou, N.Y.Williams, P.A.Hadfield, A.T.

(2008) J Mol Biol 384: 165

  • DOI: 10.1016/j.jmb.2008.09.028
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Maleyl pyruvate isomerase (MPI) is a bacterial glutathione S-transferase (GST) from the pathway for degradation of naphthalene via gentisate that enables the bacterium Ralstonia to use polyaromatic hydrocarbons as a sole carbon source. Genome sequenc ...

    Maleyl pyruvate isomerase (MPI) is a bacterial glutathione S-transferase (GST) from the pathway for degradation of naphthalene via gentisate that enables the bacterium Ralstonia to use polyaromatic hydrocarbons as a sole carbon source. Genome sequencing projects have revealed the presence of large numbers of GSTs in bacterial genomes, often located within gene clusters encoding the degradation of different aromatic compounds. This structure is therefore an example of this under-represented class of enzymes. Unlike many glutathione transferases, the reaction catalysed by MPI is an isomerisation of an aromatic ring breakdown product, and glutathione is a true cofactor rather than a substrate in the reaction. We have solved the structure of the enzyme in complex with dicarboxyethyl glutathione, an analogue of a proposed reaction intermediate, at a resolution of 1.3 A. The structure provides direct evidence that the glutathione thiolate attacks the substrate in the C2 position, with the terminal carboxylate buried at the base of the active site cleft. Our structures suggest that the C1-C2 bond remains fixed so when rotation occurs around the C2-C3 bond the atoms from C4 onwards actually move. We identified a conserved arginine that is likely to stabilize the enolate form of the substrate during the isomerisation. Arginines at either side of the active site cleft can interact with the end of the substrate/product and preferentially stabilise the product. MPI has significant sequence similarity to maleylacetoacetate isomerase (MAAI), which performs an analogous reaction in the catabolism of phenylalanine and tyrosine. The proposed mechanism therefore has relevance to the MAAIs. Significantly, whilst the overall sequence identity is 40% only one of the five residues from the Zeta motif in the active site is conserved. We re-examined the roles of the residues in the active site of both enzymes and the Zeta motif itself.


    Related Citations: 
    • A Gene Cluster Encoding Steps in Conversion of Naphthalene to Gentisate in Pseudomonas Sp. Strain U2.
      Fuenmayor, S.L., Wild, M., Boyes, A.L., Williams, P.A.
      (1998) J Bacteriol 180: 2522

    Organizational Affiliation

    Department of Biochemistry and Centre for Molecular Recognition, University of Bristol, School of Medical Sciences, University Walk, Bristol BS81TD, UK.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MALEYLPYRUVATE ISOMERASE
A, B
213Ralstonia sp. U2Mutation(s): 0 
EC: 5.2.1.2 (PDB Primary Data), 5.2.1.4 (UniProt)
Find proteins for O86043 (Ralstonia sp)
Go to UniProtKB:  O86043
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GSH
Query on GSH

Download CCD File 
A, B
GLUTATHIONE
C10 H17 N3 O6 S
RWSXRVCMGQZWBV-WDSKDSINSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.211 
  • R-Value Observed: 0.214 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 60.332α = 90
b = 81.733β = 90
c = 88.187γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling
BEASTphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-09-16
    Type: Initial release
  • Version 1.1: 2011-05-07
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance