Purification, N-terminal amino acid sequence and partial characterization of a Cu,Zn superoxide dismutase from the pathogenic fungus Aspergillus fumigatus

Free Radic Res. 1995 Jun;22(6):519-31. doi: 10.3109/10715769509150324.


A superoxide dismutase (SOD) has been purified to homogeneity from the fungal pathogen Aspergillus fumigatus using a combination of cell homogenization, isoelectric focusing and gel filtration FPLC. The N-terminal amino acid sequence of the purified enzyme demonstrated substantial homology to known Cu,Zn superoxide dismutases for a range of organisms, including Neurospora crassa and Saccharomyces cerevisiae. The enzyme subunit has a pI of 5.9, a relative molecular mass of 19 kDa and a spectral absorbance maximum of 550nm. The non reduced enzyme has a relative molecular mass of 95 kDa. The enzyme remained active after prolonged incubation at 70 degrees C and was pH insensitive in the range 7-11. Potassium cyanide and diethyldithiocarbamate, known Cu,Zn SOD inhibitors, caused inhibition of the purified enzyme at working concentrations of 0.25 mM, whilst sodium azide and o-phenanthroline demonstrated inhibition at higher concentrations (10-30 mM). SOD activity was also detectable in culture filtrate of A. fumigatus. This enzyme may have a potential role as a virulence factor in the avoidance of neutrophil and phagocyte oxidative burst killing mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Aspergillus fumigatus / enzymology*
  • Enzyme Stability
  • Hot Temperature
  • Hydrogen-Ion Concentration
  • Molecular Sequence Data
  • Superoxide Dismutase / chemistry
  • Superoxide Dismutase / isolation & purification*


  • Superoxide Dismutase