In enzymology, a 5-carboxymethyl-2-hydroxymuconate Delta-isomerase () is an enzyme that catalyzes the chemical reaction
Hence, this enzyme has one substrate, 5-carboxymethyl-2-hydroxymuconate, and one product, 5-carboxy-2-oxohept-3-enedioate.
This enzyme belongs to the family of isomerases, specifically those intramolecular oxidoreductases transposing C=C bonds. The systematic name of this enzyme class is 5-carboxymethyl-2-hydroxymuconate Delta2,Delta4-2-oxo,Delta3-isomerase. This enzyme participates in tyrosine metabolism and benzoate degradation via hydroxylation.
As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes , , , and .