Enzymes of Amino Acid Metabolism in Normal Human Skin Ii. Alanine and Aspartate Transaminases*

drogenase in normal human skin. In comparison with glutamate dehydrogenase, which catalyzes reversible oxidative deamination, the transaminases catalyze transfer of amino groups, usually from an amino acid to a ketoacid, without net loss of nitrogen. In other words, transamination represents the intermolecular exchange of amino nitrogen. Transamination plays a significant role in metabolism by providing numerous alternative pathways between amino acids. Obviously, it is a useful process for tissues, by which excessive amounts of certain amino acids can be removed rapidly without storage, and the amino acids of body protein deaminated to serve as energy sources upon oxidation via the citric acid cycle in ease of calorie