label: acetylserotonin O-methyltransferase activity
label_lc: acetylserotonin o-methyltransferase activity
description: "Catalysis of the reaction: S-adenosyl-L-methionine + N-acetylserotonin = S-adenosyl-L-homocysteine + melatonin. Melatonin is also known as N-acetyl-5-methoxytryptamine."