5D9M

Crystal structure of PbGH5A, a glycoside hydrolase family 5 enzyme from Prevotella bryantii B14, E280A mutant in complex with the xyloglucan tetradecasaccharide XXXGXXXG


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.173 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure-Function Analysis of a Mixed-linkage beta-Glucanase/Xyloglucanase from the Key Ruminal Bacteroidetes Prevotella bryantii B14.

McGregor, N.Morar, M.Fenger, T.H.Stogios, P.Lenfant, N.Yin, V.Xu, X.Evdokimova, E.Cui, H.Henrissat, B.Savchenko, A.Brumer, H.

(2016) J.Biol.Chem. 291: 1175-1197

  • DOI: 10.1074/jbc.M115.691659
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The recent classification of glycoside hydrolase family 5 (GH5) members into subfamilies enhances the prediction of substrate specificity by phylogenetic analysis. However, the small number of well characterized members is a current limitation to und ...

    The recent classification of glycoside hydrolase family 5 (GH5) members into subfamilies enhances the prediction of substrate specificity by phylogenetic analysis. However, the small number of well characterized members is a current limitation to understanding the molecular basis of the diverse specificity observed across individual GH5 subfamilies. GH5 subfamily 4 (GH5_4) is one of the largest, with known activities comprising (carboxymethyl)cellulases, mixed-linkage endo-glucanases, and endo-xyloglucanases. Through detailed structure-function analysis, we have revisited the characterization of a classic GH5_4 carboxymethylcellulase, PbGH5A (also known as Orf4, carboxymethylcellulase, and Cel5A), from the symbiotic rumen Bacteroidetes Prevotella bryantii B14. We demonstrate that carboxymethylcellulose and phosphoric acid-swollen cellulose are in fact relatively poor substrates for PbGH5A, which instead exhibits clear primary specificity for the plant storage and cell wall polysaccharide, mixed-linkage β-glucan. Significant activity toward the plant cell wall polysaccharide xyloglucan was also observed. Determination of PbGH5A crystal structures in the apo-form and in complex with (xylo)glucan oligosaccharides and an active-site affinity label, together with detailed kinetic analysis using a variety of well defined oligosaccharide substrates, revealed the structural determinants of polysaccharide substrate specificity. In particular, this analysis highlighted the PbGH5A active-site motifs that engender predominant mixed-linkage endo-glucanase activity vis à vis predominant endo-xyloglucanases in GH5_4. However the detailed phylogenetic analysis of GH5_4 members did not delineate particular clades of enzymes sharing these sequence motifs; the phylogeny was instead dominated by bacterial taxonomy. Nonetheless, our results provide key enzyme functional and structural reference data for future bioinformatics analyses of (meta)genomes to elucidate the biology of complex gut ecosystems.


    Organizational Affiliation

    From the Michael Smith Laboratories and Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
B-1,4-endoglucanase
A, B
353Prevotella bryantiiMutation(s): 1 
Find proteins for O06842 (Prevotella bryantii)
Go to UniProtKB:  O06842
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
BGC
Query on BGC

Download SDF File 
Download CCD File 
A, B
BETA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-VFUOTHLCSA-N
 Ligand Interaction
XYS
Query on XYS

Download SDF File 
Download CCD File 
A, B
XYLOPYRANOSE
C5 H10 O5
SRBFZHDQGSBBOR-LECHCGJUSA-N
 Ligand Interaction
GLC
Query on GLC

Download SDF File 
Download CCD File 
A, B
ALPHA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-DVKNGEFBSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.173 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 77.431α = 90.00
b = 81.677β = 90.00
c = 108.492γ = 90.00
Software Package:
Software NamePurpose
PHENIXphasing
HKL-3000data reduction
Cootmodel building
PHENIXrefinement
HKL-3000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-11-04
    Type: Initial release
  • Version 1.1: 2015-11-11
    Type: Database references