Spermine oxidase (SMOX)

Flavoenzyme that catalyzes the oxidation of spermine to spermidine. Can also use N(1)-acetylspermine and spermidine as substrates, with different affinity depending on the isoform (isozyme) and on the experimental conditions.

Plays an essential 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. May contribute to beta-alanine production through aldehyde dehydrogenase conversion of 3-amino-propanal.