[Purification and study of two superoxide dismutases of the mushroom Pleurotus olearius].

Two different superoxide dismutases have been purified from the luminous fungus Pleurotus olearius. The second enzyme SODm presents structural differences with the first enzyme SODc previously described [5]: it has a molecular weight of 78,000 and is composed of identical subunits (20,000); it contains also two functional Mn atoms. Using an antiserum prepared against SODc, we have shown that there is no cross-reaction between these two proteins. Spectral studies of the first enzyme SODc suggest that the active center contains trivalent manganese Mn-III.