IUBMB Enzyme Nomenclature


Accepted name: spermine oxidase

Reaction: spermine + O2 + H2O = spermidine + 3-aminopropanal + H2O2

Other name(s): PAOh1/SMO; PAOh1 (ambiguous); AtPAO1; AtPAO4; SMO; mSMO; SMO(PAOh1); SMO/PAOh1; SMO5; mSMOmu

Systematic name: spermidine:oxygen oxidoreductase (spermidine-forming)

Comments: The enzyme from Arabidopsis thaliana (AtPAO1) oxidizes norspermine to norspermidine with high efficiency [3]. The mammalian enzyme, encoded by the SMOX gene, is a cytosolic enzyme that catalyses the oxidation of spermine at the exo (three-carbon) side of the tertiary amine. No activity with spermidine. Weak activity with N1-acetylspermine. A flavoprotein (FAD). Differs in specificity from EC (N1-acetylpolyamine oxidase), EC [polyamine oxidase (propane-1,3-diamine-forming)], EC [N8-acetylspermidine oxidase (propane-1,3-diamine-forming)] and EC (non-specific polyamine oxidase).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:


1. Murray-Stewart, T., Wang, Y., Goodwin, A., Hacker, A., Meeker, A. and Casero, R.A., Jr. Nuclear localization of human spermine oxidase isoforms - possible implications in drug response and disease etiology. FEBS J. 275 (2008) 2795-2806. [PMID: 18422650]

2. Cervelli, M., Polticelli, F., Federico, R. and Mariottini, P. Heterologous expression and characterization of mouse spermine oxidase. J. Biol. Chem. 278 (2003) 5271-5276. [PMID: 12458219]

3. Tavladoraki, P., Rossi, M.N., Saccuti, G., Perez-Amador, M.A., Polticelli, F., Angelini, R. and Federico, R. Heterologous expression and biochemical characterization of a polyamine oxidase from Arabidopsis involved in polyamine back conversion. Plant Physiol. 141 (2006) 1519-1532. [PMID: 16778015]

4. Wang, Y., Murray-Stewart, T., Devereux, W., Hacker, A., Frydman, B., Woster, P.M. and Casero, R.A., Jr. Properties of purified recombinant human polyamine oxidase, PAOh1/SMO. Biochem. Biophys. Res. Commun. 304 (2003) 605-611. [PMID: 12727196]

[EC created 2009]

Return to EC 1.5.3 home page
Return to EC 1.5 home page
Return to EC 1 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page