Tyrosine

Tyrosine is a non essential white crystalline amino acid (C₉H₁₁NO₃) with an uncharged polar side chain. Its three letter code is Tyr and its single letter amino acid code is Y. Its side chain consists of an aromatic ring and a hydroxyl group which is polar ^[1]. It's formed from the hydrolysis of proteins for example, casein. It is also a precursor for epinephrine, thyroxine and melanin.