Format

Send to

Choose Destination
Phys Chem Chem Phys. 2018 Jan 24;20(4):2363-2372. doi: 10.1039/c7cp06829h.

A charge polarization model for the metal-specific activity of superoxide dismutases.

Author information

1
Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK. kevin.waldron@newcastle.ac.uk.
2
Department of Biochemistry, Biophysics and Structural Biology, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS UMR 9198, CEA-Saclay, Gif-sur-Yvette, F-91198, France. sun.un@cea.fr.

Abstract

The pathogenicity of Staphylococcus aureus is enhanced by having two superoxide dismutases (SODs): a Mn-specific SOD and another that can use either Mn or Fe. Using 94 GHz electron-nuclear double resonance (ENDOR) and electron double resonance detected (ELDOR)-NMR we show that, despite their different metal-specificities, their structural and electronic similarities extend down to their active-site 1H- and 14N-Mn(ii) hyperfine interactions. However these interactions, and hence the positions of these nuclei, are different in the inactive Mn-reconstituted Escherichia coli Fe-specific SOD. Density functional theory modelling attributes this to a different angular position of the E. coli H171 ligand. This likely disrupts the Mn-H171-E170' triad causing a shift in charge and in metal redox potential, leading to the loss of activity. This is supported by the correlated differences in the Mn(ii) zero-field interactions of the three SOD types and suggests that the triad is important for determining metal specific activity.

PMID:
29308487
PMCID:
PMC5901066
DOI:
10.1039/c7cp06829h
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Royal Society of Chemistry Icon for PubMed Central
Loading ...
Support Center