Phenylalanine ammonia-lyase

In enzymology, a phenylalanine ammonia-lyase is an enzyme that catalyzes the chemical reaction


 * L-phenylalanine $$\rightleftharpoons$$ trans-cinnamate + NH3

Hence, this enzyme has one substrate, L-phenylalanine, and two products, trans-cinnamate and NH3.

This enzyme belongs to the family of lyases, specifically ammonia lyases, which cleave carbon-nitrogen bonds. The systematic name of this enzyme class is L-phenylalanine ammonia-lyase (trans-cinnamate-forming). Other names in common use include tyrase, phenylalanine deaminase, tyrosine ammonia-lyase, L-tyrosine ammonia-lyase, phenylalanine ammonium-lyase, PAL, and L-phenylalanine ammonia-lyase. This enzyme participates in 5 metabolic pathways: tyrosine metabolism, phenylalanine metabolism, nitrogen metabolism, phenylpropanoid biosynthesis, and alkaloid biosynthesis ii.

Structural studies
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes, , , , and.