2Q9H

Crystal structure of the C73S mutant of diaminopimelate epimerase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.199 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Dynamics of catalysis revealed from the crystal structures of mutants of diaminopimelate epimerase.

Pillai, B.Cherney, M.Diaper, C.M.Sutherland, A.Blanchard, J.S.Vederas, J.C.James, M.N.G.

(2007) Biochem.Biophys.Res.Commun. 363: 547-553

  • DOI: 10.1016/j.bbrc.2007.09.012
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Diaminopimelate (DAP) epimerase catalyzes the stereoinversion of ll-DAP to meso-DAP, a precursor of l-lysine and an essential component of the bacterial peptidoglycan. This function is vital to bacteria and the enzyme therefore represents an attracti ...

    Diaminopimelate (DAP) epimerase catalyzes the stereoinversion of ll-DAP to meso-DAP, a precursor of l-lysine and an essential component of the bacterial peptidoglycan. This function is vital to bacteria and the enzyme therefore represents an attractive target for the design of novel anti-bacterials. DAP epimerase belongs to the group of PLP-independent amino acid racemases that function through a rather unusual mechanism involving two cysteines acting in concert as a base (thiolate) and an acid (thiol). We have solved the crystal structures of the apo-forms of DAP epimerase mutants (C73S and C217S) from Haemophilus influenzae at 2.3A and 2.2A resolution, respectively. These structures provide a snapshot of the enzyme in the first step of the catalytic cycle. Comparisons with the structures of the inhibitor-bound form reveal that the enzyme adopts an 'open conformation' in the absence of substrates or inhibitors with the two active site cysteines existing as a thiol-thiolate pair. Substrate binding to the C-terminal domain triggers the closure of the N-terminal domain coupled with tight encapsulation of the ligand, stabilization of the conformation of an active site loop containing Cys73 and expulsion of water molecules with concomitant desolvation of the thiolate base. This structural rearrangement is critical for catalysis.


    Organizational Affiliation

    Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alta, Canada T6G 2H7.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Diaminopimelate epimerase
A
274Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd)Mutation(s): 1 
Gene Names: dapF
EC: 5.1.1.7
Find proteins for P44859 (Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd))
Go to UniProtKB:  P44859
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
TLA
Query on TLA

Download SDF File 
Download CCD File 
A
L(+)-TARTARIC ACID
C4 H6 O6
FEWJPZIEWOKRBE-JCYAYHJZSA-N
 Ligand Interaction
ACY
Query on ACY

Download SDF File 
Download CCD File 
A
ACETIC ACID
C2 H4 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.199 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 100.910α = 90.00
b = 114.047β = 90.00
c = 66.777γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
CNSrefinement
DENZOdata reduction
Blu-Icedata collection
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-10-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2012-02-22
    Type: Structure summary