Chloridazon-catechol dioxygenase

Chloridazon-catechol dioxygenase (EC 1.13.11.36) is an enzyme that catalyzes the chemical reaction

5-amino-4-chloro-2-(2,3-dihydroxyphenyl)-3(2H)-pyridazinone + O₂ 5-amino-4-chloro-2-(2-hydroxymuconoyl)-3(2H)-pyridazinone

Thus, the two substrates of this enzyme are 5-amino-4-chloro-2-(2,3-dihydroxyphenyl)-3(2H)-pyridazinone and oxygen, whereas its product is 5-amino-4-chloro-2-(2-hydroxymuconoyl)-3(2H)-pyridazinone.

This enzyme belongs to the family of oxidoreductases, specifically those acting on single donors with O₂ as oxidant and incorporation of two atoms of oxygen into the substrate (oxygenases). The oxygen incorporated need not be derived from O₂. The systematic name of this enzyme class is 5-amino-4-chloro-2-(2,3-dihydroxyphenyl)-3(2H)-pyridazinone 1,2-oxidoreductase (decyclizing). It employs one cofactor, iron.

References

• Muller R, Haug S, Eberspacher J, Lingens F (1977). "[Catechol 2,3-dioxygenase from pyrazon-degrading bacteria (author's transl)]". Hoppe. Seylers. Z. Physiol. Chem. 358 (7): 797–805. doi:10.1515/bchm2.1977.358.2.797. PMID 19349. 
• Muller R, Schmitt S, Lingens F (1982). "A novel non-heme iron-containing dioxygenase. Chloridazon-catechol dioxygenase from Phenylobacterium immobilis DSM 1986". Eur. J. Biochem. 125 (3): 579–84. doi:10.1111/j.1432-1033.1982.tb06722.x. PMID 6811270.