Hydroxyquinol 1,2-dioxygenase () is an enzyme isolated from Trichosporon cutaneum that catalyzes the chemical reaction
The two substrates of this enzyme are hydroxyquinol and oxygen. Its product is 3-hydroxy-cis,cis-muconic acid.
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 benzene-1,2,4-triol:oxygen 1,2-oxidoreductase (decyclizing). This enzyme is also called hydroxyquinol dioxygenase. This enzyme participates in benzoate degradation via hydroxylation and 1,4-dichlorobenzene degradation. It employs one cofactor, iron.
, only one structure has been solved for this class of enzymes, with the PDB accession code .