1WVG

Structure of CDP-D-glucose 4,6-dehydratase from Salmonella typhi


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of CDP-D-glucose 4,6-dehydratase from Salmonella typhi complexed with CDP-D-xylose.

Koropatkin, N.M.Holden, H.M.

(2005) Acta Crystallogr.,Sect.D 61: 365-373

  • DOI: 10.1107/S0907444904033876

  • PubMed Abstract: 
  • Tyvelose is a unique 3,6-dideoxyhexose found in the O antigens of some pathogenic species of Yersinia and Salmonella. It is produced via a complex biochemical pathway that employs CDP-D-glucose as the starting ligand. CDP-D-glucose 4,6-dehydratase ca ...

    Tyvelose is a unique 3,6-dideoxyhexose found in the O antigens of some pathogenic species of Yersinia and Salmonella. It is produced via a complex biochemical pathway that employs CDP-D-glucose as the starting ligand. CDP-D-glucose 4,6-dehydratase catalyzes the first irreversible step in the synthesis of this 3,6-dideoxysugar by converting CDP-D-glucose to CDP-4-keto-6-deoxyglucose via an NAD+ -dependent intramolecular oxidation-reduction reaction. Here, the cloning, protein purification and X-ray crystallographic analysis of CDP-D-glucose 4,6-dehydratase from Salmonella typhi complexed with the substrate analog CDP-D-xylose are described. Each subunit of the tetrameric enzyme folds into two domains. The N-terminal region contains a Rossmann fold and provides the platform for NAD(H) binding. The C-terminal motif is primarily composed of alpha-helices and houses the binding pocket for the CDP portion of the CDP-D-xylose ligand. The xylose moiety extends into the active-site cleft that is located between the two domains. Key residues involved in anchoring the sugar group to the protein include Ser134, Tyr159, Asn197 and Arg208. Strikingly, Ser134 O gamma and Tyr159 O eta sit within 2.9 A of the 4'-hydroxyl group of xylose. Additionally, the side chains of Asp135 and Lys136 are located at 3.5 and 3.2 A, respectively, from C-5 of xylose. In the structurally related dTDP-D-glucose 4,6-dehydratase, the Asp/Lys pair is replaced with an Asp/Glu couple. On the basis of this investigation, it can be speculated that Tyr159 serves as the catalytic base to abstract the 4'-hydroxyl proton from the sugar and that Asp135 and Lys136 play critical roles in the subsequent dehydration step that leads to the final product.


    Organizational Affiliation

    Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706-1544, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CDP-glucose 4,6-dehydratase
A, B
359Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)Mutation(s): 0 
Gene Names: rfbG
EC: 4.2.1.45
Find proteins for P26397 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Go to UniProtKB:  P26397
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
APR
Query on APR

Download SDF File 
Download CCD File 
A, B
ADENOSINE-5-DIPHOSPHORIBOSE
C15 H23 N5 O14 P2
SRNWOUGRCWSEMX-KEOHHSTQSA-N
 Ligand Interaction
CXY
Query on CXY

Download SDF File 
Download CCD File 
A
CYTIDINE-5'-DIPHOSPHO-BETA-D-XYLOSE
C14 H23 N3 O15 P2
NWSKPSPTJOAICE-OCIMBMBZSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.201 
  • Space Group: P 31 2 1
Unit Cell:
Length (Å)Angle (°)
a = 93.900α = 90.00
b = 93.900β = 90.00
c = 152.800γ = 120.00
Software Package:
Software NamePurpose
HKL-2000data collection
SCALEPACKdata scaling
AMoREphasing
HKL-2000data reduction
TNTrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-01-26
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance