1QHZ

NATIVE TETRAGONAL STRUCTURE OF THE ENDOGLUCANASE CEL5A FROM BACILLUS AGARADHAERENS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.206 
  • R-Value Work: 0.172 
  • R-Value Observed: 0.172 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Insights into ligand-induced conformational change in Cel5A from Bacillus agaradhaerens revealed by a catalytically active crystal form.

Varrot, A.Schulein, M.Davies, G.J.

(2000) J Mol Biol 297: 819-828

  • DOI: 10.1006/jmbi.2000.3567
  • Primary Citation of Related Structures:  
    1QHZ, 1QI0, 1QI2

  • PubMed Abstract: 
  • Glycoside hydrolases are ubiquitous enzymes involved in a diverse array of biological processes, from the breakdown of biomass, through to viral invasion and cellular signalling. Endoglucanase Cel5A from Bacillus agaradhaerens, classified into glycoside hydrolase family 5, has been studied in a catalytically inactive crystal form at low pH conditions, in which native and complex structures revealed the importance of ring distortion during catalysis ...

    Glycoside hydrolases are ubiquitous enzymes involved in a diverse array of biological processes, from the breakdown of biomass, through to viral invasion and cellular signalling. Endoglucanase Cel5A from Bacillus agaradhaerens, classified into glycoside hydrolase family 5, has been studied in a catalytically inactive crystal form at low pH conditions, in which native and complex structures revealed the importance of ring distortion during catalysis. Here, we present the structure of Cel5A in a new crystal form obtained at higher pH values in which the enzyme is active "in-crystal". Native, cellotriosyl-enzyme intermediate and beta-d-cellobiose structures were solved at 1.95, 1.75 and 2.1 A resolution, respectively. These structures reveal two classes of conformational change: those caused by crystal-packing and pH, with others induced upon substrate binding. At pH 7 a histidine residue, His206, implicated in substrate-binding and catalysis, but previously far removed from the substrate-binding cleft, moves over 10 A into the active site cleft in order to interact with the substrate in the +2 subsite. Occupation of the -1 subsite by substrate induces a loop closure to optimise protein-ligand interactions. Cel5A, along with the unrelated family 45 and family 6 cellulases, provides further evidence of substantial conformational change in response to ligand binding for this class of hydrolytic enzyme.


    Organizational Affiliation

    Department of Chemistry Structural Biology Laboratory University of York, Heslington, Y010 5DD, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ENDOGLUCANASE BA305Salipaludibacillus agaradhaerensMutation(s): 0 
Gene Names: cel5A
EC: 3.2.1.4
UniProt
Find proteins for O85465 (Salipaludibacillus agaradhaerens)
Explore O85465 
Go to UniProtKB:  O85465
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.206 
  • R-Value Work: 0.172 
  • R-Value Observed: 0.172 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.54α = 90
b = 74.54β = 90
c = 135.93γ = 90
Software Package:
Software NamePurpose
AMoREphasing
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-06-07
    Type: Initial release
  • Version 1.1: 2007-10-16
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance