THe enzyme 3,4-dihydroxyphthalate decarboxylase (EC 4.1.1.69) catalyzes the chemical reaction

3,4-dihydroxyphthalate 3,4-dihydroxybenzoate + CO₂

This enzyme belongs to the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is 3,4-dihydroxyphthalate carboxy-lyase (3,4-dihydroxybenzoate-forming). This enzyme is also called 3,4-dihydroxyphthalate carboxy-lyase.

• Eaton RW, Ribbons DW (1982). "Metabolism of dibutylphthalate and phthalate by Micrococcus sp. strain 12B". J. Bacteriol. 151 (1): 48–57. PMC 220188. PMID 7085570.