Merck, MAK484-1KT, Phenylalanine Assay Kit

Phenylalanine is an essential amino acid and an important precursor for several key signal molecules such as dopamine, norepinephrine, epinephrine, and the skin pigment melanin. It is found naturally in the breast milk of mammals and used as nutritional supplements in food and drink products. The genetic disorder phenylketonuria is the inability to metabolize phenylalanine. Individuals with this disorder are known as \phenylketonurics\. Individuals who cannot metabolize phenylalanine must monitor their intake of protein to control the buildup of phenylalanine.