Metabolism of L-aspartic acid.

Aspartic acid, like glutamic acid, occupies a central position in amino acid metabolism. In most tissues it takes part in the transamination reaction (1). In the liver and the kidney, where all amino acids undergo cleamination, the rate of this process for aspartic acid is second only to glutamic acid (2). For these reasons, one would expect the exchange of amino nitrogen of aspartic acid with the nitrogen of the metabolic pool to be more rapid than in the case of other amino acids. This is indeed true, as the present experiment with isotopic L-aspartic acid shows.