title: 2-Chloro-1,4-dimethoxybenzene cation radical: formation and role in the lignin peroxidase oxidation of anisyl alcohol.
abstract: 2-Chloro-1,4-dimethoxybenzene (2Cl-1,4-DMB) oxidation by lignin peroxidase (LiP) proceeds via the formation of the 2Cl-1,4-DMB cation radical as indicated by ESR and UV/vis spectroscopy. The products of the LiP-catalyzed oxidation of 2Cl-1,4-DMB were identified as 2-chloro-1,4-benzoquinone and the dimers dichlorotetramethoxybiphenyl and chloro(chlorodimethoxyphenyl)benzoquinone. The addition of anisyl alcohol (AA) rapidly quenched the 2Cl-1,4-DMB cation radical optical absorption bands, suggesting that the cation radical directly mediates the oxidation of AA. When LiP reactions are conducted in the presence of 50 microM 2Cl-1,4-DMB, the enzyme is inactivated; however, this inactivation can be prevented by the addition of AA. This also suggests that the 2Cl-1,4-DMB cation radical formed in the reaction, in turn, oxidizes AA.
authors.affiliation: Department of Food Technology and Nutritional Sciences, Wageningen Agricultural University, 6700 EV Wageningen, The Netherlands.
authors.forename: P J
authors.initials: PJ
authors.lastname: Teunissen
authors.forename: D
authors.initials: D
authors.lastname: Sheng
authors.forename: G V
authors.initials: GV
authors.lastname: Reddy
authors.forename: P
authors.initials: P
authors.lastname: Moënne-Loccoz
authors.forename: J A
authors.initials: JA
authors.lastname: Field
authors.forename: M H
authors.initials: MH
authors.lastname: Gold
mesh_terms: D000840:Anisoles / Q000737:chemistry / Q000378:metabolism*; D016227:Benzoquinones / Q000378:metabolism; D019905:Benzyl Alcohol / Q000378:metabolism; D002412:Cations / Q000737:chemistry / Q000378:metabolism; D002722:Chlorobenzenes / Q000737:chemistry / Q000378:metabolism*; D003067:Coenzymes; D019281:Dimerization; D004578:Electron Spin Resonance Spectroscopy; D006207:Half-Life; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007700:Kinetics; D013058:Mass Spectrometry; D016877:Oxidants / Q000494:pharmacology; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020075:Phanerochaete / Q000378:metabolism*
chemical_list: D000840:Anisoles; D016227:Benzoquinones; D002412:Cations; D002722:Chlorobenzenes; D003067:Coenzymes; D016877:Oxidants; C116014:2-chloro-1,4-dimethoxybenzene; C107221:2-chloro-1,4-benzoquinone; C066943:anisyl alcohol; D006861:Hydrogen Peroxide; D010544:Peroxidases; C042858:lignin peroxidase; D019905:Benzyl Alcohol