3II1

Structural characterization of difunctional glucanase-xylanse CelM2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.170 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural characterization of the bifunctional glucanase-xylanase CelM2 reveals the metal effect and substrate-binding moiety

Nam, K.H.Lee, W.H.Rhee, K.H.Hwang, K.Y.

(2010) Biochem.Biophys.Res.Commun. 391: 1726-1730

  • DOI: 10.1016/j.bbrc.2009.12.141

  • PubMed Abstract: 
  • The bifunctional glycoside hydrolase enzyme, CelM2, is able to hydrolyze glucan and xylan effectively. The crystal structure of this protein has been determined, providing useful sequential and structural information [K.H. Nam, S.J. Kim, K.Y. Hwang, ...

    The bifunctional glycoside hydrolase enzyme, CelM2, is able to hydrolyze glucan and xylan effectively. The crystal structure of this protein has been determined, providing useful sequential and structural information [K.H. Nam, S.J. Kim, K.Y. Hwang, Crystal structure of CelM2, a bifunctional glucanase-xylanase protein from a metagenome library, Biochem. Biophys. Res. Commun. 383 (2009) 183-186]. In addition, this protein is a good model for understanding bifunctional enzymes, and it will provide information relevant for genetic engineering that will be useful in the design of bifunctional proteins. However, previous structural characterization was not sufficient to develop an understanding of the metal ion and substrate-binding moiety. Herein, we determined the metal-binding site of CelM2 using zinc ions. Our results revealed that the zinc ions participate in the crystallographic packing and enzyme folding of the external region of the TIM-like barrel domain. Based on our structure, zinc ions induce the passive form of the CAP region at the catalytic cleft of the CelM2 protein. Moreover, glucose was bound to the CelM2 structure at the catalytic site. This structure provides the binding moiety that binds to the hydroxyl group of substrates such as cellulose. In addition, a structural comparison of celM2 with Cel44 provides a good model of the binding mode of CelM2. Thus, our study represents a novel structural characterization of the metal-binding site and the structure of the complex formed between CelM2 and its substrate.


    Organizational Affiliation

    Division of Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul 136-701, Republic of Korea.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cellulase
A
535uncultured bacteriumMutation(s): 0 
Gene Names: celM2
Find proteins for A1E9A6 (uncultured bacterium)
Go to UniProtKB:  A1E9A6
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
BGC
Query on BGC

Download SDF File 
Download CCD File 
A
BETA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-VFUOTHLCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.170 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 86.594α = 90.00
b = 87.431β = 90.00
c = 110.574γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data collection
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2009-07-31 
  • Released Date: 2009-08-25 
  • Deposition Author(s): Hwang, K.Y., Nam, K.H.

Revision History 

  • Version 1.0: 2009-08-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance