4A05

Structure of the catalytic core domain of the cellobiohydrolase, Cel6A, from Chaetomium thermophilum


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.197 
  • R-Value Work: 0.167 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the Catalytic Core Module of the Chaetomium Thermophilum Family Gh6 Cellobiohydrolase Cel6A.

Thompson, A.J.Heu, T.Shaghasi, T.Benyamino, R.Jones, A.Friis, E.P.Wilson, K.S.Davies, G.J.

(2012) Acta Crystallogr.,Sect.D 68: 875

  • DOI: 10.1107/S0907444912016496

  • PubMed Abstract: 
  • Cellulases, including cellobiohydrolases and endoglucanases, are important enzymes involved in the breakdown of the polysaccharide cellulose. These catalysts have found widescale industrial applications, particularly in the paper and textile industri ...

    Cellulases, including cellobiohydrolases and endoglucanases, are important enzymes involved in the breakdown of the polysaccharide cellulose. These catalysts have found widescale industrial applications, particularly in the paper and textile industries, and are now finding use in `second-generation' conversion of biomass to biofuels. Despite this considerable biotechnological application, and undoubted future potential, uncertainty remains as to the exact reaction mechanism of the inverting cellulases found in the GH6 family of carbohydrate-active enzymes. In order to gain additional understanding as to how these societally beneficial biocatalysts function, the crystal structure of a GH6 cellobiohydrolase from Chaetomium thermophilum, CtCel6A, has been solved. This structure reveals a distorted α/β-barrel fold comprising a buried tunnel-like active site quite typical of Cel6A enzymes. Analysis of an enzyme-product complex (cellobiose in the -3 and -2 subsites and cellotetraose in subsites +1 to +4) supports the hypothesis that this group of enzymes act via an atypical single-displacement mechanism. Of particular note in this analysis is an active-centre metal ion, Li(+), the position of which matches the position of the positively charged anomeric carbon of the oxocarbenium-ion-like transition state.


    Organizational Affiliation

    Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, England.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CELLOBIOHYDROLASE FAMILY 6
A
364Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)Mutation(s): 0 
EC: 3.2.1.-
Find proteins for G0SD43 (Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719))
Go to UniProtKB:  G0SD43
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CBI
Query on CBI

Download SDF File 
Download CCD File 
A
CELLOBIOSE
C12 H22 O11
GUBGYTABKSRVRQ-QRZGKKJRSA-N
 Ligand Interaction
CTT
Query on CTT

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Download CCD File 
A
beta-D-glucopyranosyl-(1->4)-beta-D-glucopyranosyl-(1->4)-beta-D-glucopyranosyl-(1->4)-beta-D-glucopyranose
CELLOTETRAOSE
C24 H42 O21
LUEWUZLMQUOBSB-HGDSAIHNSA-N
 Ligand Interaction
LI
Query on LI

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Download CCD File 
A
LITHIUM ION
Li
HBBGRARXTFLTSG-UHFFFAOYSA-N
 Ligand Interaction
NAG
Query on NAG

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Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.197 
  • R-Value Work: 0.167 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 49.710α = 90.00
b = 76.060β = 90.00
c = 107.240γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
SCALAdata scaling
MOSFLMdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-07-25
    Type: Initial release
  • Version 1.1: 2012-08-01
    Type: Structure summary
  • Version 1.2: 2012-08-15
    Type: Database references