1OVW

ENDOGLUCANASE I COMPLEXED WITH NON-HYDROLYSABLE SUBSTRATE ANALOGUE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.284 
  • R-Value Work: 0.197 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the Fusarium oxysporum endoglucanase I with a nonhydrolyzable substrate analogue: substrate distortion gives rise to the preferred axial orientation for the leaving group.

Sulzenbacher, G.Driguez, H.Henrissat, B.Schulein, M.Davies, G.J.

(1996) Biochemistry 35: 15280-15287

  • DOI: 10.1021/bi961946h

  • PubMed Abstract: 
  • Endoglucanase I (EG I) is a cellulase, from glycosyl hydrolase family 7, which cleaves the beta-1,4 linkages of cellulose with overall retention of configuration. The structure of the EG I from Fusarium oxysproum, complexed to a nonhydrolyzable thioo ...

    Endoglucanase I (EG I) is a cellulase, from glycosyl hydrolase family 7, which cleaves the beta-1,4 linkages of cellulose with overall retention of configuration. The structure of the EG I from Fusarium oxysproum, complexed to a nonhydrolyzable thiooligosaccharide substrate analogue, has been determined by X-ray crystallography at a resolution of 2.7 A utilizing the 4-fold noncrystallographic symmetry present in the asymmetric unit. The electron density map clearly reveals the presence of three glucosyl units of the inhibitor, consistent with the known number of sugar-binding subsites, located at the active site of the enzyme in the -2, -1, and +1 subsites, i.e., actually spanning the point of enzymatic cleavage. The pyranose ring at the point of potential enzymatic cleavage is clearly distorted from the standard 4C1 chair as was originally suggested for beta-retaining enzymes by Phillips [Ford, L.O., Johnson, L.N., Machin, P. A., Phillips, D.C., & Tijan, T. (1974) J. Mol. Biol, 88, 349-371]. The distortion observed goes beyond the "sofa" conformation observed in previous studies and results in a conformation whose salient feature is the resulting quasi-axial orientation for the glycosidic bond and leaving group, as predicted by stereoelectronic theory. An almost identical conformation has recently been observed in a complex of chitobiase with its unhydrolyzed substrate [Tews, I., Perrakis, A., Oppenheim, A., Dauter, Z., Wilson, K. S., & Vorgias, C. E. (1996) Nat. Struct. Biol. 3, 638-648]. The striking similarity between these two complexes extends beyond the almost identical pyranose ring distortion. The overlap of the two respective sugars places the enzymatic nucleophile of endoglucanase I in coincidence with the C2 acetamido oxygen of N-acetylglucosamine in the catalytic site of the chitobiase, substantiating the involvement of this group in the catalytic mechanism of chitobiase and related chitinolytic enzymes. The endoglucanase I complex with the thiosaccharide substrate analogue clearly illustrates the potential of nonhydrolyzable sulfur-linked oligosaccharides in the elucidation of substrate binding and catalysis by glycosyl hydrolases.


    Related Citations: 
    • 4-Thiocellooligosaccharides: Their Synthesis and Use as Inhibitors of Cellulases Inhibitors of Cellulases
      Schou, C.,Rasmussen, G.,Schulein, M.,Henrissat, B.,Driguez, H.
      (1993) J.Carbohydr.Chem. 12: 743
    • The Use of Conserved Cellulase Family-Specific Sequences to Clone Cellulase Homologue Cdnas from Fusarium Oxysporum
      Sheppard, P.O.,Grant, F.J.,Oort, P.J.,Sprecher, C.A.,Foster, D.C.,Hagen, F.S.,Upshall, A.,Mcknight, G.L.,O'Hara, P.J.
      (1994) Gene 150: 163


    Organizational Affiliation

    Department of Chemistry, University of York, Heslington, England.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ENDOGLUCANASE I
A, B, C, D
398Fusarium oxysporumEC: 3.2.1.4
Find proteins for P46237 (Fusarium oxysporum)
Go to UniProtKB:  P46237
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
DP5
Query on DP5

Download SDF File 
Download CCD File 
A, B, C, D
1,4-DIMERCAPTO-ALPHA-D-GLUCOPYRANOSYL-(1-4)-S-1,4-DIMERCAPTO-BETA-D-GLUCOPYRANOSYL-(1-4)-S-1,4-DIMERCAPTO-BETA-D-GLUCOPYRANOSE
C18 H32 O12 S4
WBVXJPVNEKGLBK-FBMSAYSMSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B, C, D
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
PCA
Query on PCA
A, B, C, D
L-PEPTIDE LINKINGC5 H7 N O3GLU
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.284 
  • R-Value Work: 0.197 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 68.155α = 90.00
b = 78.279β = 96.89
c = 142.461γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1997-10-29
    Type: Initial release
  • Version 1.1: 2008-03-03
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance