Tyrosine (from the Greek tyros, for "cheese", where it was first discovered) is one of the 20 amino acids that are used by cells to synthesize proteins. It plays a key role in signal transduction, since 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 a precursor in the synthesis of the thyroid hormone, thyroxin.
- Isoelectric point: 5.64
- Mass: 181.19
- Abbreviations: Tyr / Y
- Side chain: hydrophilic
- Chemical formula: C9O3H11N (structure)