It is known that the monoamine oxidase (MAO) enzyme plays an important part in the metabolism of catecholamine neurotransmitters. In what way does the enzyme inactivate these neurotransmitters (norepinephrine, epinephrine, dopamine)?

Answer options

1. Addition of an amino group
2. Removal of a methyl group
3. Hydrolysis
4. Oxidative deamination
5. Carboxylation

Explanation

MAO only catalyze Oxidative deamination of monoamines (Oxygen is used to remove an amine group from a molecule, resulting in aldehyde and ammonia).