EC - Phenylalanine/tyrosine ammonia-lyase

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IntEnz Enzyme Nomenclature


Accepted name:
phenylalanine/tyrosine ammonia-lyase
Other names:
bifunctional PAL
Systematic name:
L-phenylalanine(or L-tyrosine):trans-cinnamate(or trans-p-hydroxycinnamate) ammonia-lyase




This enzyme is a member of the aromatic amino acid lyase family, other members of which are EC (histidine ammonia-lyase), EC (tyrosine ammonia-lyase) and EC (phenylalanine ammonia-lyase). The enzyme from some monocots, including maize, and from the yeast Rhodosporidium toruloides, deaminate L-phenylalanine and L-tyrosine with similar catalytic efficiency [3]. The enzyme contains the cofactor 3,5-dihydro-5-methylidene-4H-imidazol-4-one (MIO), which is common to this family [3]. This unique cofactor is formed autocatalytically by cyclization and dehydration of the three amino-acid residues alanine, serine and glycine [4].

Links to other databases

Enzymes and pathways: NC-IUBMB , BRENDA , ExplorEnz , ENZYME@ExPASy , KEGG , MetaCyc , UniPathway
Protein domains and families: PROSITE:PDOC00424
Structural data: CSA , EC2PDB
Gene Ontology: GO:0045548 , GO:0052883


  1. Rösler, J., Krekel, F., Amrhein, N. and Schmid, J.
    Maize phenylalanine ammonia-lyase has tyrosine ammonia-lyase activity.
    Plant Physiol. 113: 175-179 (1997). [PMID: 9008393]
  2. Watts, K.T., Mijts, B.N., Lee, P.C., Manning, A.J. and 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: 1317-1326 (2006). [PMID: 17185227]
  3. Louie, G.V., Bowman, M.E., Moffitt, M.C., Baiga, T.J., Moore, B.S. and Noel, J.P.
    Structural determinants and modulation of substrate specificity in phenylalanine-tyrosine ammonia-lyases.
    Chem. Biol. 13: 1327-1338 (2006). [PMID: 17185228]
  4. Schwede, T.F., Rétey, J. and Schulz, G.E.
    Crystal structure of histidine ammonia-lyase revealing a novel polypeptide modification as the catalytic electrophile.
    Biochemistry 38: 5355-5361 (1999). [PMID: 10220322]

[EC created 2008 (EC created 1965, part-incorporated 2008)]