1RWB

Cooperative Effect of Two Surface Amino Acid Mutations (Q252L and E170K) of Glucose Dehydrogenase from Bacillus megaterium IWG3 for the stabilization of Oligomeric State


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.224 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Cooperative effect of two surface amino acid mutations (Q252L and E170K) in glucose dehydrogenase from Bacillus megaterium IWG3 on stabilization of its oligomeric state.

Baik, S.H.Michel, F.Aghajari, N.Haser, R.Harayama, S.

(2005) Appl.Environ.Microbiol. 71: 3285-3293

  • DOI: 10.1128/AEM.71.6.3285-3293.2005

  • PubMed Abstract: 
  • A thermostable glucose dehydrogenase (GlcDH) mutant of Bacillus megaterium IWG3 harboring the Q252L substitution (Y. Makino, S. Negoro, I. Urabe, and H. Okada, J. Biol. Chem. 264:6381-6385, 1989) is stable at pH values above 9, but only in the presen ...

    A thermostable glucose dehydrogenase (GlcDH) mutant of Bacillus megaterium IWG3 harboring the Q252L substitution (Y. Makino, S. Negoro, I. Urabe, and H. Okada, J. Biol. Chem. 264:6381-6385, 1989) is stable at pH values above 9, but only in the presence of 2 M NaCl. Another GlcDH mutant exhibiting increased stability at an alkaline pH in the absence of NaCl has been isolated previously (S.-H. Baik, T. Ide, H. Yoshida, O. Kagami, and S. Harayama, Appl. Microbiol. Biotechnol. 61:329-335, 2003). This mutant had two amino acid substitutions, Q252L and E170K. In the present study, we characterized three GlcDH mutants harboring the substitutions Q252L, E170K, and Q252L/E170K under low-salt conditions. The GlcDH mutant harboring two substitutions, Q252L/E170K, was stable, but mutants harboring a single substitution, either Q252L or E170K, were unstable at an alkaline pH. Gel filtration chromatography analyses demonstrated that the oligomeric state of the Q252/E170K enzyme was stable, while the tetramers of the enzymes harboring a single substitution (Q252L or E170K) dissociated into dimers at an alkaline pH. These results indicated that the Q252L and E170K substitutions synergistically strengthened the interaction at the dimer-dimer interface. The crystal structure of the E170K/Q252L mutant, determined at 2.0-angstroms resolution, showed that residues 170 and 252 are located in a hydrophobic cavity at the subunit-subunit interface. We concluded that these residues in the wild-type enzyme have thermodynamically unfavorable effects, while the Q252L and E170K substitutions increase the subunit-subunit interactions by stabilizing the hydrophobic cavity.


    Organizational Affiliation

    Marine Biotechnology Institute, Heita Kamaishi, Iwate 026-0001, Japan. baik-sangho@nite.go.jp




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Glucose 1-dehydrogenase
A, B, E, F
261Bacillus megateriumEC: 1.1.1.47
Find proteins for P40288 (Bacillus megaterium)
Go to UniProtKB:  P40288
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAD
Query on NAD

Download SDF File 
Download CCD File 
A, B, E, F
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.224 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 118.500α = 90.00
b = 65.400β = 92.60
c = 118.000γ = 90.00
Software Package:
Software NamePurpose
CNSphasing
MOSFLMdata reduction
CCP4data scaling
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-12-30
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance