2E22

Crystal structure of xanthan lyase in complex with mannose


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.165 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A Structural Factor Responsible for Substrate Recognition by Bacillus sp. GL1 Xanthan Lyase that Acts Specifically on Pyruvated Side Chains of Xanthan

Maruyama, Y.Mikami, B.Hashimoto, W.Murata, K.

(2007) Biochemistry 46: 781-791

  • DOI: 10.1021/bi0619775
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Xanthan is a bacterial heteropolysaccharide composed of pentasaccharide repeating units, i.e., a cellobiose as a backbone and a trisaccharide consisting of two mannoses and one glucuronic acid as a side chain. Nonreducing terminal mannose residues of ...

    Xanthan is a bacterial heteropolysaccharide composed of pentasaccharide repeating units, i.e., a cellobiose as a backbone and a trisaccharide consisting of two mannoses and one glucuronic acid as a side chain. Nonreducing terminal mannose residues of xanthan side chains are partially pyruvated. Bacillus sp. GL1 xanthan lyase, a member of polysaccharide lyase family 8, acts specifically on pyruvated side chains of xanthan and yields pyruvated mannose through a beta-elimination reaction by using a single Tyr255 residue as base and acid catalysts. Here we show structural factors for substrate recognition by xanthan lyase through X-ray crystallographic and mutational analyses. The enzyme accommodates mannose and pyruvated mannose at the -1 subsite, although both inhibitor and dissociation constants of the two monosaccharides indicated that the affinity of pyruvated mannose for xanthan lyase is much higher than that of mannose. The high affinity of pyruvated mannose is probably due to the formation of additional hydrogen bonds between the carboxyl group of pyruvated mannose and amino acid residues of Tyr315 and Arg612. Site-directed mutagenesis of the two residues demonstrated that Arg612 is a key residue in recognizing pyruvated mannose. Arg612 is located in the protruding loop covering the substrate, suggesting that the loop functions as a lid that is responsible for the proper accommodation of the substrate at the active site.


    Organizational Affiliation

    Laboratory of Basic and Applied Molecular Biotechnology, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Xanthan lyase
A
752Bacillus sp. (strain GL1)Mutation(s): 0 
Gene Names: xly
EC: 4.2.2.12
Find proteins for Q9AQS0 (Bacillus sp. (strain GL1))
Go to UniProtKB:  Q9AQS0
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MAN
Query on MAN

Download SDF File 
Download CCD File 
A
ALPHA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-PQMKYFCFSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
MANKi: 837000000 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.165 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 54.358α = 90.00
b = 91.462β = 90.00
c = 159.653γ = 90.00
Software Package:
Software NamePurpose
CNSphasing
FRAMBOdata collection
SAINTdata scaling
CNSrefinement
SAINTdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-01-30
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance