1A39

HUMICOLA INSOLENS ENDOCELLULASE EGI S37W, P39W DOUBLE-MUTANT


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.170 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

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: 91-100

  • Also Cited By: 1DYM

  • PubMed Abstract: 
  • Family 7 of the glycosyl hydrolases contains both endoglucanases and cellobiohydrolases. In addition to their different catalytic activities on crystalline substrates, the cellobiohydrolases differ from the endoglucanases in their activity on longer ...

    Family 7 of the glycosyl hydrolases contains both endoglucanases and cellobiohydrolases. In addition to their different catalytic activities on crystalline substrates, the cellobiohydrolases differ from the endoglucanases in their activity on longer soluble substrates, indicative of a greater number of subsites on the enzyme. A double mutant (S37W, P39W) of the Humicola insolens endoglucanase I (EG I) has been constructed in order to mimic aspects of the subsite structure of the corresponding family 7 cellobiohydrolase, cellobiohydrolase-I (CBH I). The 3-D crystal structure of the double mutant has been solved and refined to a crystallographic R-factor of 0.17 at a resolution of 2.2 A (1 A = 0.1 nm). The two mutant tryptophans are clearly visible in the electron density and are in the same orientation as those found in the substrate binding groove of CBH I. In addition to the substitutions, the C-terminal amino acids (399QELQ), disordered in the native enzyme structure, are clearly visible and there are a small number of minor loop movements associated with differences in crystal packing. Kinetic determinations show that the S37W, P39W mutant EG I has almost identical activity, compared to native EG I, on small soluble cellodextrins. On phosphoric acid swollen cellulose there is a small (30%), but significant, decrease in the apparent KM indicating that the double mutant may indeed exhibit stronger binding to longer polymeric substrates.


    Organizational Affiliation

    Department of Chemistry, University of York, Heslington, UK. davies@yorvic.york.ac.uk




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ENDOGLUCANASE I
A
402Humicola insolensMutation(s): 0 
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: 2.2 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.170 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 50.960α = 90.00
b = 81.400β = 90.00
c = 94.770γ = 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: 1999-03-02
    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