3,4-Dihydroxyphenylacetic acid (DOPAC) is a metabolite of the neurotransmitter dopamine. Dopamine can be metabolized into one of three substances. One such substance is DOPAC. Another is 3-methoxytyramine (3-MT). Both of these substances are degraded to form

homovanillic acid Homovanillic acid (HVA) is a major catecholamine metabolite that is produced by a consecutive action of monoamine oxidase and catechol-O-methyltransferase on dopamine. Homovanillic acid is used as a reagent to detect oxidative enzymes, and is ass ...

(HVA). Both degradations involve the enzymes monoamine oxidase (MAO) and

catechol-O-methyl transferase Catechol-''O''-methyltransferase (COMT; ) is one of several enzymes that degrade catecholamines (neurotransmitters such as dopamine, epinephrine, and norepinephrine), catecholestrogens, and various drugs and substances having a catechol struct ...

(COMT), albeit in reverse order: MAO catalyzes dopamine to DOPAC, and COMT catalyzes DOPAC to HVA; whereas COMT catalyzes dopamine to 3-MT and MAO catalyzes 3-MT to HVA. The third metabolic end-product of dopamine is

norepinephrine Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad' ...

(noradrenaline). DOPAC can be oxidized by

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%� ...

, leading to the formation of toxic metabolites which destroy dopamine storage vesicles in the substantia nigra. This may contribute to the failure of levodopa treatment of

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...

. A

MAO-B Monoamine oxidase B, also known as MAOB, is an enzyme that in humans is encoded by the ''MAOB'' gene. The protein encoded by this gene belongs to the flavin monoamine oxidase family. It is an enzyme located in the outer mitochondrial membrane. I ...

inhibitor such as selegiline or

rasagiline Rasagiline (Azilect, Azipron) is an irreversible inhibitor of monoamine oxidase-B used as a monotherapy to treat symptoms in early Parkinson's disease or as an adjunct therapy in more advanced cases. The racemic form of the drug was invented b ...

can prevent this from happening. It can also be found in the bark of ''

Eucalyptus globulus ''Eucalyptus globulus'', commonly known as southern blue gum or blue gum, is a species of tall, evergreen tree endemic to southeastern Australia. This ''Eucalyptus'' species has mostly smooth bark, juvenile leaves that are whitish and waxy on ...

''. This product has been synthesized (52% yield) from

4-hydroxyphenylacetic acid 4-Hydroxyphenylacetic acid is a chemical compound found in olive oil and beer. Synthesis 4-Hydroxyphenylacetic acid is obtained by reducing 4-hydroxymandelic acid with elemental phosphorus and iodine. Uses In industry, 4-hydroxyphenylacetic ac ...

via

aerobic Aerobic means "requiring air," in which "air" usually means oxygen. Aerobic may also refer to * Aerobic exercise, prolonged exercise of moderate intensity * Aerobics, a form of aerobic exercise * Aerobic respiration, the aerobic process of cel ...

biotransformation Biotransformation is the biochemical modification of one chemical compound or a mixture of chemical compounds. Biotransformations can be conducted with whole cells, their lysates, or purified enzymes. Increasingly, biotransformations are effected w ...

using whole cell cultures of ''

Arthrobacter protophormiae ''Glutamicibacter protophormiae'' is a bacterium belonging to the genus '' Glutamicibacter''. It contains a glycolipid 3- 'O''-α-D-mannopyranosyl-(1→3)-''O''-α-D-mannopyranosyl''sn''-1,2-diglyceride (DMDG). It has peptidoglycan type A4α wit ...

''.

References

{{DEFAULTSORT:Dihydroxyphenylacetic acid, 3,4- Phenolic human metabolites Acetic acids Catechols