Isolation of Manganese-containing Superoxide Dismutase from Bacillus subtilis

Abstract

Bacillus subtilis is regarded as one of the most important bacteria in the food industry. Next to Mycobacterium lepraemurium, B. subtilis (IFO 3022) is the best bacterial producer of superoxide dismutase. The B. subtilis superoxide dismutase was purified 40-fold to homogeneity from a cellfree extract using ammonium sulfate fractionation and DEAE-Toyopearl and Sephadex G-150 chromatography. The enzyme has a molecular weight of 45, 000 and consists of two subunits identical in molecular weight. The enzyme, which exhibits absorption maxima at 280 and 470nm, contains 1.13g atoms of Mn per mol of enzyme as the catalytically active metal.