Catechol-O-methyltransferase (COMT) inhibitors are a class of medication used in combination with levodopa and carbidopa in the treatment of symptoms of Parkinson's disease (PD).

monoamine oxidase and catechol-O-methyltransferase

In generally, replicase includes polymerse, helicase, and methyltransferase. So they are not the same.

There are actually two enzymes that breakdown dopamine:

1) MAO-B (monoamine oxidase B)

2) COMT (carboxy-O-methyltransferase)

Melatonin is made from serotonin (5-hydroxytryptamine) and N-acetylserotonin in the pineal gland by arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase.