3-Chloro-L-tyrosine

3-Chloro-L-tyrosine is a specific marker of myeloperoxidase-catalyzed oxidation, and is markedly elevated in low density lipoprotein isolated from human atherosclerotic intima.
3-chloro-L-tyrosine is a chloroamino acid comprising a tyrosine core with a chloro- substituent ortho to the phenolic hydroxy group. It has a role as a biomarker and a human metabolite. It is a chloroamino acid, a member of monochlorobenzenes, a L-tyrosine derivative and a non-proteinogenic L-alpha-amino acid.|3-Chlorotyrosine is a specific biomarker of hypochlorous acid (HClO), the oxidation product of myeloperoxidase (MPO). Under oxidative stress, 3-chlorotyrosine is produced in proteins with tyrosine residues by the strong oxidant HClO. HClO which is formed at sites of inflammation is also the anti-bacterial molecule produced by neutrophils through MPO-catalyzed oxidation. MPO is a heme-containing enzyme secreted by activated neutrophils and monocytes; it is the only enzyme that produces HClO. Therefore, 3-chlorotyrosine can potentially be used to help determine the extent of neutrophilic inflammation.