Tyrosine

Tyrosine (named after Greek tyros (cheese), where it was first discovered) is an amino acid (see there for chemical structure). It is one of the 20 amino acids that are used by cells to synthesize proteins. It plays a key role in signal transduction, as it can be tagged with a phosphate group by protein kinases (phosphorylated?) to alter the functionality and/or activity of enzymes. Another important biological function of Tyrosine is as the precursor for the synthesis of the thyroid hormone Thyroxine?.

Chemical properties:

• Isoelectric point : 5.64
• Mass : 181.19
• Abbreviations : Tyr / Y
• Side chain : hydrophilic
• Chemical formula : C₉O₃H₁₁N