1DYM

Humicola insolens Endocellulase Cel7B (EG 1) E197A Mutant


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.200 
  • R-Value Work: 0.158 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal Structure of the Family 7 Endoglucanase I (Cel7B) from Humicola Insolens at 2.2 A Resolution and Identification of the Catalytic Nucleophile by Trapping of the Covalent Glycosyl-Enzyme Intermediate.

Mackenzie, L.F.Sulzenbacher, G.Divne, C.Jones, T.A.Woldike, H.F.Schulein, M.Withers, S.G.Davies, G.J.

(1998) Biochem.J. 335: 409

  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Cellulose is the major polysaccharide component of the plant cell wall and the most abundant naturally produced macromolecule on Earth. The enzymic degradation of cellulose, by cellulases, is therefore of great environmental and commercial significan ...

    Cellulose is the major polysaccharide component of the plant cell wall and the most abundant naturally produced macromolecule on Earth. The enzymic degradation of cellulose, by cellulases, is therefore of great environmental and commercial significance. Cellulases are found in 12 of the glycoside hydrolase families classified according to their amino acid sequence similarities. Endoglucanase I (Cel7B), from the soft-rot fungus Humicola insolens, is a family 7 enzyme. The structure of the native form of Cel7B from H. insolens at 2.2 A resolution has been solved by molecular replacement using the known Trichoderma reesei cellobiohydrolase I [Divne, Ståhlberg, Reinikainen, Ruohonen, Pettersson, Knowles, Teeri and Jones (1994) Science 265, 524-528] structure as the search model. Cel7B catalyses hydrolysis of the beta-1,4 glycosidic linkages in cellulose with net retention of anomeric configuration. The catalytic nucleophile at the active site of Cel7B has been identified as Glu-197 by trapping of a 2-deoxy-2-fluorocellotriosyl enzyme intermediate and identification of the labelled peptide in peptic digests by tandem MS. Site-directed mutagenesis of both Glu-197 and the prospective catalytic acid, Glu-202, results in inactive enzyme, confirming the critical role of these groups for catalysis.


    Related Citations: 
    • Oligosaccharide Specificity of a Family 7 Endoglucanase: Insertion of Potential Sugar-Binding Subsites
      Davies, G.J.,Ducros, V.,Lewis, R.J.,Borchert, T.V.,Schulein, M.
      (1997) J.Biotechnol. 57: 91


    Organizational Affiliation

    Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ENDOGLUCANASE I
A
402Humicola insolensMutation(s): 1 
Gene Names: CEL7B
EC: 3.2.1.4
Find proteins for P56680 (Humicola insolens)
Go to UniProtKB:  P56680
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

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

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.200 
  • R-Value Work: 0.158 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 49.969α = 90.00
b = 74.284β = 103.82
c = 60.146γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-02-04
    Type: Initial release
  • Version 1.1: 2014-01-29
    Type: Database references, Derived calculations, Non-polymer description, Other, Structure summary, Version format compliance