1HGW

CEL6A D175A mutant


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.183 
  • R-Value Observed: 0.183 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

The Active Site of Cellobiohydrolase Cel6A from Trichoderma Reesei: The Roles of Aspartic Acids D221 and D175

Koivula, A.Ruohonen, L.Wohlfahrt, G.Reinikainen, T.Teeri, T.T.Piens, K.Claeyssens, M.Weber, M.Vasella, A.Becker, D.Sinnott, M.L.Zou, J.-Y.Kleywegt, G.J.Szardenings, M.Stahlberg, J.Jones, T.A.

(2002) J Am Chem Soc 124: 10015

  • DOI: 10.1021/ja012659q
  • Primary Citation of Related Structures:  
    1HGW, 1HGY

  • PubMed Abstract: 
  • Trichoderma reesei cellobiohydrolase Cel6A is an inverting glycosidase. Structural studies have established that the tunnel-shaped active site of Cel6A contains two aspartic acids, D221 and D175, that are close to the glycosidic oxygen of the scissil ...

    Trichoderma reesei cellobiohydrolase Cel6A is an inverting glycosidase. Structural studies have established that the tunnel-shaped active site of Cel6A contains two aspartic acids, D221 and D175, that are close to the glycosidic oxygen of the scissile bond and at hydrogen-bonding distance from each other. Here, site-directed mutagenesis, X-ray crystallography, and enzyme kinetic studies have been used to confirm the role of residue D221 as the catalytic acid. D175 is shown to affect protonation of D221 and to contribute to the electrostatic stabilization of the partial positive charge in the transition state. Structural and modeling studies suggest that the single-displacement mechanism of Cel6A may not directly involve a catalytic base. The value of (D2O)(V) of 1.16 +/- 0.14 for hydrolysis of cellotriose suggests that the large direct effect expected for proton transfer from the nucleophilic water through a water chain (Grotthus mechanism) is offset by an inverse effect arising from reversibly breaking the short, tight hydrogen bond between D221 and D175 before catalysis.


    Related Citations: 
    • Three-Dimensional Structure of Cellobiohydrolase II from Trichoderma Reesei
      Rouvinen, J., Bergfors, T., Teeri, T., Knowles, J.K., Jones, T.A.
      (1990) Science 249: 380

    Organizational Affiliation

    VTT Biotechnology, P.O. Box 1500, FIN-02044 VTT, Espoo, Finland.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CELLOBIOHYDROLASE CEL6A (FORMERLY CALLED CBH II)AB365Trichoderma reeseiMutation(s): 1 
Gene Names: CBH2 (D175A)cbh2
EC: 3.2.1.91
Find proteins for P07987 (Hypocrea jecorina)
Explore P07987 
Go to UniProtKB:  P07987
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download CCD File 
A, B
2-acetamido-2-deoxy-beta-D-glucopyranose
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
MAN
Query on MAN

Download CCD File 
A, B
alpha-D-mannopyranose
C6 H12 O6
WQZGKKKJIJFFOK-PQMKYFCFSA-N
 Ligand Interaction
CO
Query on CO

Download CCD File 
A
COBALT (II) ION
Co
XLJKHNWPARRRJB-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.183 
  • R-Value Observed: 0.183 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 48.63α = 90
b = 74.72β = 103.64
c = 91.44γ = 90
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-01-15
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Data collection, Derived calculations, Other, Structure summary