catalytic activity:N(1),N(12)-diacetylspermine + O(2) + H(2)O = N(1)-acetylspermidine + 3-acetamidobutanal + H(2)O(2).,catalytic activity:N(1)-acetylspermidine + O(2) + H(2)O = putrescine + 3-acetamidopropanal + H(2)O(2).,catalytic activity:N(1)-acetylspermine + O(2) + H(2)O = spermidine + 3-acetamidopropanal + H(2)O(2).,cofactor:Binds 1 FAD per subunit.,function:Flavoenzyme which catalyzes the oxidation of N(1)-acetylspermine to spermidine and is thus involved in the polyamine back-conversion. Can also oxidize N(1)-acetylspermidine to putrescine. Substrate specificity: N(1)-acetylspermine = N(1)-acetylspermidine > N(1),N(12)-diacylspermine >> spermine. Does not oxidize spermidine. Plays an important role in the regulation of polyamine intracellular concentration and has the potential to act as a determinant of cellular sensitivity to the antitumor polyamine analogs.,induction:By polyamine analogs.,miscellaneous:Oxidizes N(1)-acetylated polyamines on the exo-side of their N(4)-amino groups. Plant PAO oxidizes spermine on the endo-side of the N(4)-nitrogen.,pathway:Amine and polyamine metabolism; spermine metabolism.,similarity:Belongs to the flavin monoamine oxidase family.,subunit:Monomer.,tissue specificity:Widely expressed. Not detected in spleen. Expressed at lower level in neoplastic tissues.,