4YHE

NATIVE BACTEROIDETES-AFFILIATED GH5 CELLULASE LINKED WITH A POLYSACCHARIDE UTILIZATION LOCUS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.212 
  • R-Value Work: 0.178 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Features of a Bacteroidetes-Affiliated Cellulase Linked with a Polysaccharide Utilization Locus.

Naas, A.E.MacKenzie, A.K.Dalhus, B.Eijsink, V.G.Pope, P.B.

(2015) Sci Rep 5: 11666-11666

  • DOI: 10.1038/srep11666
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Previous gene-centric analysis of a cow rumen metagenome revealed the first potentially cellulolytic polysaccharide utilization locus, of which the main catalytic enzyme (AC2aCel5A) was identified as a glycoside hydrolase (GH) family 5 endo-cellulase ...

    Previous gene-centric analysis of a cow rumen metagenome revealed the first potentially cellulolytic polysaccharide utilization locus, of which the main catalytic enzyme (AC2aCel5A) was identified as a glycoside hydrolase (GH) family 5 endo-cellulase. Here we present the 1.8 Å three-dimensional structure of AC2aCel5A, and characterization of its enzymatic activities. The enzyme possesses the archetypical (β/α)8-barrel found throughout the GH5 family, and contains the two strictly conserved catalytic glutamates located at the C-terminal ends of β-strands 4 and 7. The enzyme is active on insoluble cellulose and acts exclusively on linear β-(1,4)-linked glucans. Co-crystallization of a catalytically inactive mutant with substrate yielded a 2.4 Å structure showing cellotriose bound in the -3 to -1 subsites. Additional electron density was observed between Trp178 and Trp254, two residues that form a hydrophobic "clamp", potentially interacting with sugars at the +1 and +2 subsites. The enzyme's active-site cleft was narrower compared to the closest structural relatives, which in contrast to AC2aCel5A, are also active on xylans, mannans and/or xyloglucans. Interestingly, the structure and function of this enzyme seem adapted to less-substituted substrates such as cellulose, presumably due to the insufficient space to accommodate the side-chains of branched glucans in the active-site cleft.


    Organizational Affiliation

    Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, 1432 NORWAY.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
GH5
A, B
389Bacteroidetes bacterium AC2aMutation(s): 0 
Find proteins for A0A076MPD7 (Bacteroidetes bacterium AC2a)
Go to UniProtKB:  A0A076MPD7
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.212 
  • R-Value Work: 0.178 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 85.510α = 90.00
b = 100.680β = 90.00
c = 101.940γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
Aimlessdata scaling
PDB_EXTRACTdata extraction
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
The Research Council of NorwayNorway214042
The Research Council of NorwayNorway216625/F50
The Research Council of NorwayNorway190965
European Research CouncilBelgium336355
South-Eastern Norway Regional Health AuthorityNorway2012085
South-Eastern Norway Regional Health AuthorityNorway2015095

Revision History 

  • Version 1.0: 2015-05-20
    Type: Initial release
  • Version 1.1: 2015-07-15
    Type: Database references