Where are amino acids primarily catabolized in the body?

Amino acids are primarily catabolized in the liver, making it a crucial organ in protein metabolism. The liver plays a central role in the deamination process, where amino acids undergo the removal of their amino group to form ammonia and keto acids. This process is essential for the regulation of amino acid levels in the body, as well as for the conversion of amino acids into energy or other molecules.

Once deamination occurs, the ammonia produced is transported to the urea cycle in the liver, where it is converted into urea and subsequently excreted by the kidneys. In addition to deamination, the liver is responsible for synthesizing various proteins, including albumin and clotting factors, and can convert excess amino acids into glucose through gluconeogenesis or fatty acids through lipogenesis.

Although other tissues, such as muscles and kidneys, can also metabolize amino acids to some extent, the liver is the primary site where significant catabolic pathways occur, reinforcing its role as the central hub for amino acid metabolism.