On the Isolation and Purification of Structure‐bound Proteins

Abstract

Structure‐bound catalytically active proteins (mitochondrial monoamine oxidases from rat or beef liver and beef brain) have been prepared in non‐sedimentable, soluble form, without significant inactivation, by treatment of mitochondrial membranes with non‐ionic detergents in a strongly alkaline medium with benzylamine ‐ a substrate of monoamine oxidases, which protects the enzymes from inactivation by alkalis. By means of subsequent ammonium sulphate fractionation and treatment with aluminium hydroxydes, enzyme preparations have been obtained which, as evidenced by electrophoresis in polyacrylamide gel and values of specific activity, are highly purified.