4HMC

Crystal structure of cold-adapted chitinase from Moritella marina


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.190 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structure of a complete four-domain chitinase from Moritella marina, a marine psychrophilic bacterium

Malecki, P.H.Raczynska, J.E.Vorgias, C.E.Rypniewski, W.

(2013) Acta Crystallogr D Biol Crystallogr 69: 821-829

  • DOI: 10.1107/S0907444913002011
  • Primary Citation of Related Structures:  
    4HMC, 4HMD, 4HME

  • PubMed Abstract: 
  • X-ray crystallography reveals chitinase from the psychrophilic bacterium Moritella marina to be an elongated molecule which in addition to the catalytic β/α-barrel domain contains two Ig-like domains and a chitin-binding domain, all linked in a chain. A ligand-binding study using NAG oligomers showed the enzyme to be active in the crystal lattice and resulted in complexes of the protein with oxazolinium ion (the reaction intermediate) and with NAG2, a reaction product ...

    X-ray crystallography reveals chitinase from the psychrophilic bacterium Moritella marina to be an elongated molecule which in addition to the catalytic β/α-barrel domain contains two Ig-like domains and a chitin-binding domain, all linked in a chain. A ligand-binding study using NAG oligomers showed the enzyme to be active in the crystal lattice and resulted in complexes of the protein with oxazolinium ion (the reaction intermediate) and with NAG2, a reaction product. The characteristic motif DXDXE, containing three acidic amino-acid residues, which is a signature of type 18 chitinases, is conserved in the enzyme. Further analysis of the unliganded enzyme with the two protein-ligand complexes and a comparison with other known chitinases elucidated the roles of other conserved residues near the active site. Several features have been identified that are probably important for the reaction mechanism, substrate binding and the efficiency of the enzyme at low temperatures. The chitin-binding domain and the tryptophan patch on the catalytic domain provide general affinity for chitin, in addition to the affinity of the binding site; the two Ig-like domains give the protein a long reach over the chitin surface, and the flexible region between the chitin-binding domain and the adjacent Ig-like domain suggests an ability of the enzyme to probe the surface of the substrate, while the open shallow substrate-binding groove allows easy access to the active site.


    Organizational Affiliation

    Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Chitinase 60 A528Moritella marinaMutation(s): 0 
Gene Names: chi60
EC: 3.2.1.14
Find proteins for B1VBB0 (Moritella marina)
Explore B1VBB0 
Go to UniProtKB:  B1VBB0
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download Ideal Coordinates CCD File 
A
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
NA
Query on NA

Download Ideal Coordinates CCD File 
A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.190 
  • Space Group: P 31 1 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 67.622α = 90
b = 67.622β = 90
c = 257.188γ = 120
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
PHASERphasing
REFMACrefinement
PDB_EXTRACTdata extraction
MAR345dtbdata collection

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-05-01
    Type: Initial release
  • Version 1.1: 2013-05-15
    Changes: Database references