Lyases;
Carbon-nitrogen lyases;
Ammonia-lyases

L-tyrosine ammonia-lyase (trans-p-hydroxycinnamate-forming)

L-tyrosine = trans-p-hydroxycinnamate + NH3 [RN:R00737]

R00737;
(other) R06132

L-tyrosine [CPD:C00082]

This enzyme is a member of the aromatic amino acid lyase family, other members of which are EC 4.3.1.3 (histidine ammonia-lyase), EC 4.3.1.24 (phenylalanine ammonia-lyase) and EC 4.3.1.25 (phenylalanine/tyrosine ammonia-lyase). The enzyme contains the cofactor 3,5-dihydro-5-methylidene-4H-imidazol-4-one (MIO), which is common to this family [1]. This unique cofactor is formed autocatalytically by cyclization and dehydration of the three amino-acid residues alanine, serine and glycine [3]. The enzyme is far more active with tyrosine than with phenylalanine as substrate, but the substrate specificity can be switched by mutation of a single amino acid (H89F) in the enzyme from the bacterium Rhodobacter sphaeroides [1,2].

EC 4.3.1.23 created 2008 (EC 4.3.1.5 created 1965, part-incorporated 2008)

1  [PMID:17185228]

Louie GV, Bowman ME, Moffitt MC, Baiga TJ, Moore BS, Noel JP.

Structural determinants and modulation of substrate specificity in phenylalanine-tyrosine ammonia-lyases.

Chem Biol 13:1327-38 (2006)
DOI:10.1016/j.chembiol.2006.11.011

[rsp:RSP_3574]

2  [PMID:17185227]

Watts KT, Mijts BN, Lee PC, Manning AJ, Schmidt-Dannert C.

Discovery of a substrate selectivity switch in tyrosine ammonia-lyase, a member of the aromatic amino acid lyase family.

Chem Biol 13:1317-26 (2006)
DOI:10.1016/j.chembiol.2006.10.008

[rsp:RSP_3574]

3  [PMID:10220322]

Schwede TF, Retey J, Schulz GE.

Crystal structure of histidine ammonia-lyase revealing a novel polypeptide modification as the catalytic electrophile.

Biochemistry 38:5355-61 (1999)
DOI:10.1021/bi982929q