In enzymology, a glutaconyl-CoA decarboxylase () is an enzyme that catalyzes the chemical reaction
Hence, this enzyme has one substrate, (2E)-glutaconyl-CoA, and two products, (2E)-butenoyl-CoA and CO<sub>2</sub>. During the process, a sodium ion is transported across the membrane. Previously, this enzyme was classified as EC 4.1.1.70.
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 4-carboxybut-2-enoyl-CoA carboxy-lyase (but-2-enoyl-CoA-forming). Other names in common use include glutaconyl coenzyme A decarboxylase, pent-2-enoyl-CoA carboxy-lyase, and 4-carboxybut-2-enoyl-CoA carboxy-lyase. This enzyme participates in benzoate degradation via coa ligation and butanoate metabolism.
As a decarboxylase, the enzyme requires biotin for its function.
As of mid-2024, five structures have been solved for this class of enzymes, with the PDB accession codes , , , and .