1OTG

5-CARBOXYMETHYL-2-HYDROXYMUCONATE ISOMERASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Observed: 0.179 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Enzymatic ketonization of 2-hydroxymuconate: specificity and mechanism investigated by the crystal structures of two isomerases.

Subramanya, H.S.Roper, D.I.Dauter, Z.Dodson, E.J.Davies, G.J.Wilson, K.S.Wigley, D.B.

(1996) Biochemistry 35: 792-802

  • DOI: 10.1021/bi951732k
  • Primary Citation of Related Structures:  
    1OTG, 1OTF

  • PubMed Abstract: 
  • 5-Carboxymethyl-2-hydroxymuconate isomerase (CHMI) and 4-oxalocrotonate tautomerase (4-OT) are enzymes that catalyze the isomerization of unsaturated ketones. They share a common enzyme mechanism, although they show a preference for different substra ...

    5-Carboxymethyl-2-hydroxymuconate isomerase (CHMI) and 4-oxalocrotonate tautomerase (4-OT) are enzymes that catalyze the isomerization of unsaturated ketones. They share a common enzyme mechanism, although they show a preference for different substrates. There is no apparent sequence homology between the enzymes. To investigate the molecular mechanism and the basis for their substrate specificity, we have determined the crystal structures of the two enzymes at high resolution. 4-OT is hexameric, with the subunits arranged with 32 symmetry. CHMI is trimeric and has extensive contacts between subunits, which include secondary structural elements. The central core of the CHMI monomer has a fold similar to a 4-OT dimer, but the secondary structural elements that form the subunit contacts around the 3-fold axis are different in the two enzymes. The region of greatest similarity between the two enzymes is a large pocket that is proposed to be the active site. The enzymes appear to operate via a "one-base" mechanism, and the possible role of residues in this pocket is discussed in view of this idea. Finally, the molecular basis for substrate specificity in the two enzymes is discussed.


    Organizational Affiliation

    Laboratory of Molecular Biophysics, University of Oxford, U.K.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
5-CARBOXYMETHYL-2-HYDROXYMUCONATE ISOMERASEABC125Escherichia coli CMutation(s): 0 
Gene Names: CHM
EC: 5.3.2 (PDB Primary Data), 5.3.3.10 (UniProt)
Find proteins for Q05354 (Escherichia coli)
Explore Q05354 
Go to UniProtKB:  Q05354
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download CCD File 
A, B, C
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Observed: 0.179 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 90.3α = 90
b = 90.3β = 90
c = 129.8γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
PROLSQrefinement
X-PLORrefinement
MOSFLMdata reduction
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1996-04-03
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Source and taxonomy, Version format compliance