Catabolism of amino acids - Transamination, deamination, urea cycle?

Yes, transamination, deamination, and the urea cycle are all involved in the catabolism of amino acids.

Transamination is the process by which an amino group is transferred from an amino acid to a keto acid, resulting in the formation of a new amino acid and a new keto acid. This reaction is catalyzed by enzymes called transaminases or aminotransferases. Transamination allows for the interconversion of different amino acids and is an important step in amino acid metabolism.

Deamination is the removal of an amino group from an amino acid, resulting in the formation of ammonia (NH3) and a keto acid. This process can occur through different pathways, such as oxidative deamination or hydrolytic deamination. Oxidative deamination is catalyzed by the enzyme glutamate dehydrogenase and occurs primarily in the liver. Hydrolytic deamination is catalyzed by enzymes called deaminases and occurs in various tissues.

The urea cycle is a series of biochemical reactions that occur in the liver and kidneys to convert toxic ammonia into urea, which is then excreted in urine. The urea cycle involves several enzymatic steps and requires the participation of different amino acids, such as ornithine, citrulline, and arginine. The urea cycle plays a crucial role in the elimination of excess nitrogen from the body, which is derived from the catabolism of amino acids.

Overall, these processes (transamination, deamination, and the urea cycle) are essential for the breakdown of amino acids and the removal of nitrogenous waste from the body.