4HHM

Crystal structure of a mutant, G219A, of Glucose Isomerase from Streptomyces sp. SK


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.197 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Identification of critical residues for the activity and thermostability of Streptomyces sp. SK glucose isomerase.

Ben Hlima, H.Bejar, S.Riguet, J.Haser, R.Aghajari, N.

(2013) Appl.Microbiol.Biotechnol. 97: 9715-9726

  • DOI: 10.1007/s00253-013-4784-2
  • Primary Citation of Related Structures:  4HHL

  • PubMed Abstract: 
  • The role of residue 219 in the physicochemical properties of D-glucose isomerase from Streptomyces sp. SK strain (SKGI) was investigated by site-directed mutagenesis and structural studies. Mutants G219A, G219N, and G219F were generated and character ...

    The role of residue 219 in the physicochemical properties of D-glucose isomerase from Streptomyces sp. SK strain (SKGI) was investigated by site-directed mutagenesis and structural studies. Mutants G219A, G219N, and G219F were generated and characterized. Comparative studies of their physicochemical properties with those of the wild-type enzyme highlighted that mutant G219A displayed increased specific activity and thermal stability compared to that of the wild-type enzyme, while for G219N and G219F, these properties were considerably decreased. A double mutant, SKGI F53L/G219A, displayed a higher optimal temperature and a higher catalytic efficiency than both the G219A mutant and the wild-type enzyme and showed a half-life time of about 150 min at 85 °C as compared to 50 min for wild-type SKGI. Crystal structures of SKGI wild-type and G219A enzymes were solved to 1.73 and 2.15 Å, respectively, and showed that the polypeptide chain folds into two structural domains. The larger domain consists of a (β/α)8 unit, and the smaller domain forms a loop of α helices. Detailed analyses of the three-dimensional structures highlighted minor but important changes in the active site region as compared to that of the wild-type enzyme leading to a displacement of both metal ions, and in particular that in site M2. The structural analyses moreover revealed how the substitution of G219 by an alanine plays a crucial role in improving the thermostability of the mutant enzyme.


    Organizational Affiliation

    Laboratoire de Micro-organismes et de Biomolécules, Centre de Biotechnologie de Sfax, Université de Sfax, BP "1177", 3018, Sfax, Tunisia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Xylose isomerase
A, B, C, D, E, F, G, H
388Streptomyces sp. SKGene Names: xylA
EC: 5.3.1.5
Find proteins for Q9ZAI3 (Streptomyces sp. SK)
Go to UniProtKB:  Q9ZAI3
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
CO
Query on CO

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H
COBALT (II) ION
Co
XLJKHNWPARRRJB-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.197 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 85.500α = 90.00
b = 137.400β = 90.06
c = 136.600γ = 90.00
Software Package:
Software NamePurpose
BALBESphasing
ADSCdata collection
CNSrefinement
XSCALEdata scaling
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-03-27
    Type: Initial release
  • Version 1.1: 2013-07-24
    Type: Database references
  • Version 1.2: 2013-08-07
    Type: Database references
  • Version 1.3: 2013-11-13
    Type: Database references