3JS3

Crystal structure of type I 3-dehydroquinate dehydratase (aroD) from Clostridium difficile with covalent reaction intermediate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.20 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.192 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.3 of the entry. See complete history


Literature

Insights into the mechanism of type I dehydroquinate dehydratases from structures of reaction intermediates.

Light, S.H.Minasov, G.Shuvalova, L.Duban, M.E.Caffrey, M.Anderson, W.F.Lavie, A.

(2011) J Biol Chem 286: 3531-3539

  • DOI: https://doi.org/10.1074/jbc.M110.192831
  • Primary Citation of Related Structures:  
    3JS3, 3M7W, 3NNT

  • PubMed Abstract: 

    The biosynthetic shikimate pathway consists of seven enzymes that catalyze sequential reactions to generate chorismate, a critical branch point in the synthesis of the aromatic amino acids. The third enzyme in the pathway, dehydroquinate dehydratase (DHQD), catalyzes the dehydration of 3-dehydroquinate to 3-dehydroshikimate. We present three crystal structures of the type I DHQD from the intestinal pathogens Clostridium difficile and Salmonella enterica. Structures of the enzyme with substrate and covalent pre- and post-dehydration reaction intermediates provide snapshots of successive steps along the type I DHQD-catalyzed reaction coordinate. These structures reveal that the position of the substrate within the active site does not appreciably change upon Schiff base formation. The intermediate state structures reveal a reaction state-dependent behavior of His-143 in which the residue adopts a conformation proximal to the site of catalytic dehydration only when the leaving group is present. We speculate that His-143 is likely to assume differing catalytic roles in each of its observed conformations. One conformation of His-143 positions the residue for the formation/hydrolysis of the covalent Schiff base intermediates, whereas the other conformation positions the residue for a role in the catalytic dehydration event. The fact that the shikimate pathway is absent from humans makes the enzymes of the pathway potential targets for the development of non-toxic antimicrobials. The structures and mechanistic insight presented here may inform the design of type I DHQD enzyme inhibitors.


  • Organizational Affiliation

    Center for Structural Genomics of Infectious Diseases, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
3-dehydroquinate dehydratase
A, B, C, D
258Clostridioides difficile 630Mutation(s): 0 
Gene Names: aroDCD2217
EC: 4.2.1.10
UniProt
Find proteins for Q186A6 (Clostridioides difficile (strain 630))
Explore Q186A6 
Go to UniProtKB:  Q186A6
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ186A6
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

Unit Cell:
Length ( Å )Angle ( ˚ )
a = 60.472α = 90
b = 139.619β = 90.63
c = 66.774γ = 90
Software Package:
Software NamePurpose
Blu-Icedata collection
PHASERphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2009-09-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Source and taxonomy, Version format compliance
  • Version 1.2: 2017-11-01
    Changes: Refinement description
  • Version 1.3: 2023-09-06
    Changes: Data collection, Database references, Derived calculations, Refinement description