In enzymology, a chondroitin AC lyase (EC 4.2.2.5) is an enzyme that catalyzes the chemical reaction In enzymology, a chondroitin AC lyase (EC 4.2.2.5) is an enzyme that catalyzes the chemical reaction This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on polysaccharides. The systematic name of this enzyme class is chondroitin AC lyase. Other names in common use include chondroitinase (ambiguous), chondroitin sulfate lyase, chondroitin AC eliminase, chondroitin AC lyase, chondroitinase AC, and ChnAC. As of late 2007, 11 structures have been solved for this class of enzymes, with PDB accession codes 1CB8, 1HM2, 1HM3, 1HMU, 1HMW, 1RW9, 1RWA, 1RWC, 1RWF, 1RWG, and 1RWH.