MAOA, also known as Amine oxidase [flavin-containing] A. This protein catalyzes the oxidative deamination of biogenic and xenobiotic amines and has important functions in the metabolism of neuroactive and vasoactive amines in the central nervous system and peripheral tissues. MAOA preferentially oxidizes biogenic amines such as 5-hydroxytryptamine (5-HT), norepinephrine and epinephrine. Recombinant human MAOA, fused to His-tag at N-terminus, was expressed in E.coli.