The formation of spermidine from spermine by serum amine oxidase.
D008995:Monoamine Oxidase; D010088:Oxidoreductases / Q000737:chemistry*; D013095:Spermidine; D013096:Spermine / Q000737:chemistry*
D013096:Spermine; D010088:Oxidoreductases; D008995:Monoamine Oxidase; D013095:Spermidine
OXIDASES/chemistry; SPERMINE/chemistry