3-hydroxy-2-methylquinolin-4-one 2,4-dioxygenase () is an enzyme that catalyzes the chemical reaction
The two substrates of this enzyme are 3-hydroxy-2-methylquinolin-4(1H)-one and oxygen. Its products are N-acetylanthranilic acid and carbon monoxide.
This enzyme belongs to the family of oxidoreductases, specifically those acting on single donors with O<sub>2</sub> as oxidant and incorporation of two atoms of oxygen into the substrate (oxygenases). The oxygen incorporated need not be derived from O<sub>2</sub>. The systematic name of this enzyme class is 3-hydroxy-2-methyl-1H-quinolin-4-one 2,4-dioxygenase (CO-forming). This enzyme is also called (1H)-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase.