G152A mutant of Mycobacterium tuberculosis iron-superoxide dismutase.

Experimental Data Snapshot

  • Resolution: 2.90 Å
  • R-Value Work: 0.169 

wwPDB Validation   3D Report Full Report

This is version 1.4 of the entry. See complete history


X-Ray Structure Analysis of an Engineered Fe-Superoxide Dismutase Gly-Ala Mutant with Significantly Reduced Stability to Denaturant

Cooper, J.B.Saward, S.Erskine, P.T.Badasso, M.O.Wood, S.P.Zhang, Y.Young, D.B.

(1996) FEBS Lett 387: 105

  • DOI: https://doi.org/10.1016/0014-5793(96)00490-5
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    We have refined the X-ray structure of a site-directed G152A mutant of the iron-dependent superoxide dismutase from Mycobacterium tuberculosis at 2.9 angstroms resolution. The mutation which replaces a glycine residue in a surface loop with alanine was designed to alter the conformation of this loop region which has previously been shown to play a crucial structural role in quaternary interactions within the SOD tetramer. Gly-152 was targeted as it has dihedral angles (phi = 83.1 degrees, psi = -0.3 degrees) close to the left-handed alpha-helical conformation which is rarely adopted by other amino acids except asparagine. Gly-152 was replaced by alanine as it has similar size and polarity, yet has a very low tendency to adopt similar conformations. X-ray data collection on crystals of this mutant at 2.9 angstroms resolution and subsequent least-squares refinement to an R-value of 0.169 clearly establish that the loop conformation is unaffected. Fluorescence studies of guanidine hydrochloride denaturation establish that the mutant is 4 kcal/mol less stable than the wild-type enzyme. Our results indicate that strict conformational constraints imposed upon a region of polypeptide, due for example to interactions with a neighbouring subunit, may force an alanine residue to adopt this sterically hindered conformation with a consequent reduction in stability of the folded conformation.

  • Organizational Affiliation

    Department of Crystallography, Birkbeck College, University of London, UK.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D
207Mycobacterium tuberculosisMutation(s): 1 
Find proteins for P9WGE7 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WGE7 
Go to UniProtKB:  P9WGE7
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP9WGE7
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.90 Å
  • R-Value Work: 0.169 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 68.7α = 90
b = 85.6β = 99.8
c = 66.7γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-10-05
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-04-03
    Changes: Data collection, Experimental preparation, Other
  • Version 1.4: 2024-05-08
    Changes: Data collection, Database references, Derived calculations, Other