1NH6

Structure of S. marcescens chitinase A, E315L, complex with hexasaccharide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.197 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Family 18 chitinase-oligosaccharide substrate interaction: subsite preference and anomer selectivity of Serratia marcescens chitinase A.

Aronson Jr., N.N.Halloran, B.A.Alexyev, M.F.Amable, L.Madura, J.D.Pasupulati, L.Worth, C.Van Roey, P.

(2003) Biochem.J. 376: 87-95

  • DOI: 10.1042/BJ20030273

  • PubMed Abstract: 
  • The sizes and anomers of the products formed during the hydrolysis of chitin oligosaccharides by the Family 18 chitinase A (ChiA) from Serratia marcescens were analysed by hydrophilic interaction chromatography using a novel approach in which reactio ...

    The sizes and anomers of the products formed during the hydrolysis of chitin oligosaccharides by the Family 18 chitinase A (ChiA) from Serratia marcescens were analysed by hydrophilic interaction chromatography using a novel approach in which reactions were performed at 0 degrees C to stabilize the anomer conformations of the initial products. Crystallographic studies of the enzyme, having the structure of the complex of the ChiA E315L (Glu315-->Leu) mutant with a hexasaccharide, show that the oligosaccharide occupies subsites -4 to +2 in the substrate-binding cleft, consistent with the processing of beta-chitin by the release of disaccharide at the reducing end. Products of the hydrolysis of hexa- and penta-saccharides by wild-type ChiA, as well as by two mutants of the residues Trp275 and Phe396 important in binding the substrate at the +1 and +2 sites, show that the substrates only occupy sites -2 to +2 and that additional N -acetyl-D-glucosamines extend beyond the substrate-binding cleft at the reducing end. The subsites -3 and -4 are not used in this four-site binding mode. The explanation for these results is found in the high importance of individual binding sites for the processing of short oligosaccharides compared with the cumulative recognition and processive hydrolysis mechanism used to digest natural beta-chitin.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, AL 36688, USA. naronson@jaguar1.usouthal.edu




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
chitinase A
A
540Serratia marcescensGene Names: chiA
EC: 3.2.1.14
Find proteins for P07254 (Serratia marcescens)
Go to UniProtKB:  P07254
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download SDF File 
Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.197 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 78.100α = 90.00
b = 135.230β = 90.00
c = 188.070γ = 90.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
CNSrefinement
CCP4data scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-03-18
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance