diaminooxidaasin

Diaminooxidase (DAO), also known as amine oxidase or copper amine oxidase, is a copper-containing enzyme that catalyzes the oxidative deamination of primary amines. It plays a crucial role in the metabolism of biogenic amines, such as histamine, serotonin, and dopamine. In humans, DAO is primarily found in the intestine, liver, and kidneys, and is responsible for breaking down dietary histamine.

The enzymatic reaction catalyzed by DAO involves the oxidation of an amine group to an aldehyde, with the concomitant reduction of oxygen to hydrogen peroxide and the release of ammonia. This process is essential for regulating the levels of these neurotransmitters and signaling molecules in the body. A deficiency in DAO activity can lead to an accumulation of histamine, resulting in histamine intolerance, which manifests as a variety of symptoms including headaches, hives, digestive issues, and respiratory problems.

DAO is a monomeric protein that requires copper and a covalently bound topaquinone cofactor for its catalytic activity. It is also activated by pyridoxal-5'-phosphate (PLP), a form of vitamin B6. The enzyme's activity can be influenced by various factors, including dietary intake, medications, and genetic polymorphisms. Research into DAO is ongoing, focusing on its role in health and disease, and the development of potential therapeutic interventions for conditions associated with amine metabolism disorders.