Cloning, sequencing, expression and characterization of the manganese superoxide dismutase gene from Vibrio alginolyticus

The sodA gene coding for manganese superoxide dismutase from the marine mic roorganism Yibrio alginolyticus was cloned, sequenced and over-expressed in Escherichia coli using the pET206 (+) expression vector. The full-length g ene was consisted of 603bp open reading frame, which encoded a polypeptide of 201 amino acid residues, with a calculated molecular weight of 22672Da. The deduced amino acid sequence of the sodA showed considerable homology to other Mn-SODs. The recombinant enzyme was efficiently purified from crude E. coli cell lysate by the metal ion affinity chromatography. The recombina nt VAMn-SOD resisted thermo-denatutation up to 60 degrees C and was insensi tive to inhibitors such as H2O2, NaN3 and diethyldithiocarbamic acid.