Degradation of halogenated aromatic compounds.
Due to their persistence, haloaromatics are compounds of environmental concern. Aerobically, bacteria degrade these compounds by mono- or dioxygenation of the aromatic ring. The common intermediate of these reactions is (halo)catechol. Halocatechol is cleaved either intradiol (ortho-cleavage) or extradiol (meta-cleavage). In contrast to ortho-cleavage, meta-cleavage of halocatechols yields toxic metabolites. Dehalogenation may occur fortuitously during oxygenation. Specific dehalogenation of aromatic compounds is performed by hydroxylases, in which the halo-substituent is replaced by a hydroxyl group. During reductive dehalogenation, haloaromatic compounds may act as electron-acceptors. Herewith, the halosubstituent is replaced by a hydrogen atom.
Department of Environmental and Toxicological Chemistry, University of Amsterdam, The Netherlands.
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D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D006846:Hydrocarbons, Halogenated / Q000737:chemistry / Q000378:metabolism*
D006846:Hydrocarbons, Halogenated