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PDBsum entry 4l2d

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protein ligands metals Protein-protein interface(s) links
Oxidoreductase PDB id
4l2d
Jmol
Contents
Protein chains
192 a.a.
Ligands
TRE ×4
Metals
FE2 ×4
Waters ×623
PDB id:
4l2d
Name: Oxidoreductase
Title: X-ray structure of the fe(ii) form of the iron superoxide di from pseudoalteromonas haloplanktis
Structure: Superoxide dismutase [fe]. Chain: a, c, b, d. Engineered: yes
Source: Pseudoalteromonas haloplanktis. Organism_taxid: 228. Gene: sodb, pshaa1215. Expressed in: escherichia coli. Expression_system_taxid: 562
Resolution:
2.07Å     R-factor:   0.200     R-free:   0.220
Authors: I.Russo Krauss,A.Merlino,F.Sica
Key ref: A.Merlino et al. (2014). Structural and denaturation studies of two mutants of a cold adapted superoxide dismutase point to the importance of electrostatic interactions in protein stability. Biochim Biophys Acta, 1844, 632-640. PubMed id: 24440460 DOI: 10.1016/j.bbapap.2014.01.007
Date:
04-Jun-13     Release date:   26-Feb-14    
PROCHECK
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 Headers
 References

Protein chains
Pfam   ArchSchema ?
P84612  (SODF_PSEHT) -  Superoxide dismutase [Fe]
Seq:
Struc:
192 a.a.
192 a.a.
Key:    PfamA domain  Secondary structure  CATH domain

 Enzyme reactions 
   Enzyme class: E.C.1.15.1.1  - Superoxide dismutase.
[IntEnz]   [ExPASy]   [KEGG]   [BRENDA]
      Reaction: 2 superoxide + 2 H+ = O2 + H2O2
2 × superoxide
+ 2 × H(+)
= O(2)
+ H(2)O(2)
      Cofactor: Fe cation or Mn(2+) or (Zn(2+) and Cu cation)
Molecule diagrams generated from .mol files obtained from the KEGG ftp site
 Gene Ontology (GO) functional annotation 
  GO annot!
  Biological process     oxidation-reduction process   3 terms 
  Biochemical function     oxidoreductase activity     3 terms  

 

 
    Added reference    
 
 
DOI no: 10.1016/j.bbapap.2014.01.007 Biochim Biophys Acta 1844:632-640 (2014)
PubMed id: 24440460  
 
 
Structural and denaturation studies of two mutants of a cold adapted superoxide dismutase point to the importance of electrostatic interactions in protein stability.
A.Merlino, I.Russo Krauss, I.Castellano, M.R.Ruocco, A.Capasso, E.De Vendittis, B.Rossi, F.Sica.
 
  ABSTRACT  
 
A peculiar feature of the psychrophilic iron superoxide dismutase from Pseudoalteromonas haloplanktis (PhSOD) is the presence in its amino acid sequence of a reactive cysteine (Cys57). To define the role of this residue, a structural characterization of the effect of two PhSOD mutations, C57S and C57R, was performed. Thermal and denaturant-induced unfolding of wild type and mutant PhSOD followed by circular dichroism and fluorescence studies revealed that C→R substitution alters the thermal stability and the resistance against denaturants of the enzyme, whereas C57S only alters the stability of the protein against urea. The crystallographic data on the C57R mutation suggest an involvement of the Arg side chain in the formation of salt bridges on protein surface. These findings support the hypothesis that the thermal resistance of PhSOD relies on optimization of charge-charge interactions on its surface. Our study contributes to a deeper understanding of the denaturation mechanism of superoxide dismutases, suggesting the presence of a structural dimeric intermediate between the native state and the unfolded state. This hypothesis is supported by the crystalline and solution data on the reduced form of the enzyme.