1EXP

BETA-1,4-GLYCANASE CEX-CD


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.208 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystallographic observation of a covalent catalytic intermediate in a beta-glycosidase.

White, A.Tull, D.Johns, K.Withers, S.G.Rose, D.R.

(1996) Nat.Struct.Mol.Biol. 3: 149-154


  • PubMed Abstract: 
  • The three-dimensional structure of a catalytically competent glycosyl-enzyme intermediate of a retaining beta-1,4-glycanase has been determined at a resolution of 1.8 A by X-ray diffraction. A fluorinated slow substrate forms an alpha-D-glycopyranosy ...

    The three-dimensional structure of a catalytically competent glycosyl-enzyme intermediate of a retaining beta-1,4-glycanase has been determined at a resolution of 1.8 A by X-ray diffraction. A fluorinated slow substrate forms an alpha-D-glycopyranosyl linkage to one of the two invariant carboxylates, Glu 233, as supported in solution by 19F-NMR studies. The resulting ester linkage is coplanar with the cyclic oxygen of the proximal saccharide and is inferred to form a strong hydrogen bond with the 2-hydroxyl of that saccharide unit in natural substrates. The active-site architecture of this covalent intermediate gives insights into both the classical double-displacement catalytic mechanism and the basis for the enzyme's specificity.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Diffraction Analysis of the Catalytic Domain of Cex, an Exo-Beta-1,4-Glucanase and Beta-1,4-Xylanase from the Bacterium Cellulomonas Fimi
      Bedarkar, S.,Gilkes, N.R.,Kilburn, D.G.,Kwan, E.,Rose, D.R.,Miller Junior, R.C.,Warren, R.A.,Withers, S.G.
      (1992) J.Mol.Biol. 228: 693
    • Crystal Structure of the Catalytic Domain of the Beta-1,4-Glycanase Cex from Cellulomonas Fimi
      White, A.,Withers, S.G.,Gilkes, N.R.,Rose, D.R.
      (1994) Biochemistry 33: 12546


    Organizational Affiliation

    Protein Engineering Network of Centres of Excellence, Ontario Cancer Institute, Toronto, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
BETA-1,4-D-GLYCANASE CEX-CD
A
312Cellulomonas fimiGene Names: cex (xynB)
EC: 3.2.1.91, 3.2.1.8
Find proteins for P07986 (Cellulomonas fimi)
Go to UniProtKB:  P07986
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
G2F
Query on G2F

Download SDF File 
Download CCD File 
A
2-deoxy-2-fluoro-alpha-D-glucopyranose
C6 H11 F O5
ZCXUVYAZINUVJD-UKFBFLRUSA-N
 Ligand Interaction
BGC
Query on BGC

Download SDF File 
Download CCD File 
A
BETA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-VFUOTHLCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.208 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 88.172α = 90.00
b = 88.172β = 90.00
c = 81.097γ = 90.00
Software Package:
Software NamePurpose
X-PLORmodel building
XENGENdata reduction
SDMWdata collection
X-PLORphasing
SDMSdata reduction
NIELSENdata reduction
X-PLORrefinement
XUONG)data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1997-01-27
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance
  • Version 1.3: 2011-11-16
    Type: Atomic model