1O4Z

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


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.166 

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

  • 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 pol ...

    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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
beta-agarase B
A, B, C, D
346Zobellia galactanivorans (strain DSM 12802 / CIP 106680 / NCIMB 13871 / Dsij)Gene Names: agaB
EC: 3.2.1.81
Find proteins for Q9RGX8 (Zobellia galactanivorans (strain DSM 12802 / CIP 106680 / NCIMB 13871 / Dsij))
Go to UniProtKB:  Q9RGX8
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EPE
Query on EPE

Download SDF File 
Download CCD File 
A, B, C, D
4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID
HEPES
C8 H18 N2 O4 S
JKMHFZQWWAIEOD-UHFFFAOYSA-N
 Ligand Interaction
NA
Query on NA

Download SDF File 
Download CCD File 
A, B, C, D
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
B, C
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.166 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 72.448α = 90.00
b = 105.350β = 94.13
c = 97.369γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
CCP4data scaling
AMoREphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

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