EC 1.14.14.173     
Accepted name: 2,4,6-trichlorophenol monooxygenase
Reaction: (1) 2,4,6-trichlorophenol + FADH2 + O2 = 2,6-dichloro-1,4-benzoquinone + Cl- + FAD + H2O
(2) 2,6-dichlorohydroquinone + FADH2 + O2 = 2-chloro-6-hydroxy-1,4-benzoquinone + Cl- + FAD + H2O
Other name(s): tcpA (gene name)
Systematic name: 2,4,6-trichlorophenol,FADH2:oxygen oxidoreductase (dechlorinating)
Comments: The enzyme, characterized from a number of bacterial species, participates in the degradation of 2,4,6-trichlorophenol, a compound that has been used for decades as a wood preservative. The enzyme is a multifunctional flavin-dependent monooxygenase that displaces two chlorine atoms by attacking two different positions in the substrate. Each reaction catalysed by the enzyme displaces a single chlorine and results in formation of a dione, which must be reduced by FADH2 before the monooxygenase could catalyse the second reaction. The large amount of FADH2 that is required is generated by a dedicated flavin reductase (TcpB). cf. EC 1.14.14.172, 3,5,6-trichloropyridin-2-ol monooxygenase.
References:
1.  Louie, T.M., Webster, C.M. and Xun, L. Genetic and biochemical characterization of a 2,4,6-trichlorophenol degradation pathway in Ralstonia eutropha JMP134. J. Bacteriol. 184 (2002) 3492–3500. [PMID: 12057943]
[EC 1.14.14.173 created 2020]