Joint purification of mangano and cuprozinc superoxide dismutases from a single source--a simplified method.

Preliminary studies which raised questions as to the efficacy of ammonium sulfate precipitation in separating mangano from cuprozinc superoxide dismutase and the adequacy of cyanide sensitivity in monitoring such separation led to the use of electrophoresis with activity and protein staining to monitor purification. This, together with exploitation of the differing isoelectric points of the two enzymes permitting separate elution from the same DE-52 column, led to a simplified method for purification of these enzymes using the same starting material and purification steps initially. The specific activity was 2900 and 3200 units/mg protein and yields were 18 and 20% for mangano and cuprozine superoxide dismutase, respectively.