Cloning, Expression and Characterization of a Novel Iron Superoxide Dismutase from Magnetospirillum magneticum AMB-1

The gene fesod encoding iron superoxide dismutase from Magnetospirillum AMB-1 with a calculated 22kDa was cloned and efficiently expressed in Escherichia coli BL21 (DE3). The open reading frame of 597 nucleotides encoded a protein of 199 amino acids without the signal peptide sequence. Recombinant enzyme fesod was purified by IMAC (Ni2+) in a single step to electrophoretic homogeneity presented as a single protein band on SDS-PAGE. The recombinant enzyme displayed maximum activity at 25 degrees C, which was stable in the pH range from 5.4 to 8.2 and at temperature from 25 to 45 degrees C. These results suggest that fesod may have very attractive applications in cosmetics industry as an anti ageing protein in a moderate temperature range.