1O4Z

THE THREE-DIMENSIONAL STRUCTURE OF BETA-AGARASE B FROM ZOBELLIA GALACTANIVORANS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.169 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

The Three-dimensional Structures of Two {beta}-Agarases.

Allouch, J.Jam, M.Helbert, W.Barbeyron, T.Kloareg, B.Henrissat, B.Czjzek, M.

(2003) J Biol Chem 278: 47171-47180

  • DOI: 10.1074/jbc.M308313200
  • Primary Citation of Related Structures:  
    1O4Y, 1O4Z

  • PubMed Abstract: 
  • Agars are important gelifying agents for biochemical use and the food industry. To cleave the beta-1,4-linkages between beta-d-galactose and alpha-l-3,6-anhydro-galactose residues in the red algal galactans known as agars, marine bacteria produce polysaccharide hydrolases called beta-agarases ...

    Agars are important gelifying agents for biochemical use and the food industry. To cleave the beta-1,4-linkages between beta-d-galactose and alpha-l-3,6-anhydro-galactose residues in the red algal galactans known as agars, marine bacteria produce polysaccharide hydrolases called beta-agarases. Beta-agarases A and B from Zobellia galactanivorans Dsij have recently been biochemically characterized. Here we report the first crystal structure of these two beta-agarases. The two proteins were overproduced in Escherichia coli and crystallized, and the crystal structures were determined at 1.48 and 2.3 A for beta-agarases A and B, respectively. The structure of beta-agarase A was solved by the multiple anomalous diffraction method, whereas beta-agarase B was solved with molecular replacement using beta-agarase A as model. Their structures adopt a jelly roll fold with a deep active site channel harboring the catalytic machinery, namely the nucleophilic residues Glu-147 and Glu-184 and the acid/base residues Glu-152 and Glu-189 for beta-agarases A and B, respectively. The structures of the agarases were compared with those of two lichenases and of a kappa-carrageenase, which all belong to family 16 of the glycoside hydrolases in order to pinpoint the residues responsible for their widely differing substrate specificity. The relationship between structure and enzymatic activity of the two beta-agarases from Z. galactanivorans Dsij was studied by analysis of the degradation products starting with different oligosaccharides. The combination of the structural and biochemical results allowed the determination of the number of subsites present in the catalytic cleft of the beta-agarases.


    Organizational Affiliation

    Architecture et Fonction des Macromolécules Biologiques, UMR 6098, Centre National de la Recherche Scientifique and Universités Aix-Marseille I and II, 31 Chemin Joseph Aiguier, F-13402 Marseille Cedex 20, France.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
beta-agarase BA, B, C, D346Zobellia galactanivoransMutation(s): 0 
Gene Names: agaBzobellia_3573
EC: 3.2.1.81
UniProt
Find proteins for Q9RGX8 (Zobellia galactanivorans (strain DSM 12802 / CCUG 47099 / CIP 106680 / NCIMB 13871 / Dsij))
Explore Q9RGX8 
Go to UniProtKB:  Q9RGX8
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.169 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 72.448α = 90
b = 105.35β = 94.13
c = 97.369γ = 90
Software Package:
Software NamePurpose
AMoREphasing
REFMACrefinement
DENZOdata reduction
CCP4data scaling

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2003-12-09
    Type: Initial release
  • Version 1.1: 2008-04-26
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance