Pentachlorophenol monooxygenase (, pentachlorophenol dechlorinase, pentachlorophenol dehalogenase, pentachlorophenol 4-monooxygenase, PCP hydroxylase, pentachlorophenol hydroxylase, PcpB, PCB 4-monooxygenase, PCB4MO) is an enzyme with systematic name pentachlorophenol,NADPH:oxygen oxidoreductase (hydroxylating, dechlorinating). It catalyses two different chemical reactions, depending on its substrate. In each case, the starting material is a phenol.
Pentachlorophenol monooxygenase is a flavoprotein.
The enzyme acts only on phenols with halogens in the position next to the hydroxy group on the benzene ring, the 2-position.
In this case, a typical reaction converts 2,3,5,6-tetrachlorophenol to tetrachlorohydroquinone:
In this case, a typical reaction converts pentachlorophenol to chloranil: