title: Cometabolic transformation of cis-1,2-dichloroethylene and cis-1,2-dichloroethylene epoxide by a butane-grown mixed culture.
abstract: Aerobic cometabolism of cis-1,2-dichloroethylene (c-DCE) by a butane-grown mixed culture was evaluated in batch kinetic tests. The transformation of c-DCE resulted in the coincident generation of c-DCE epoxide. Chloride release studies showed approximately 75% oxidative dechlorination of c-DCE. Mass spectrometry confirmed the presence of a compound with mass-to-charge-fragment ratios of 112, 83, 48, and 35. These values are in agreement with the spectra of chemically synthesized c-DCE epoxide. The transformation of c-DCE required O2, was inhibited by butane and was inactivated by acetylene (a known monooxygenase inactivator), indicating that a butane monooxygenase enzyme was likely involved in the transformation of c-DCE. This study showed c-DCE epoxide was biologically transformed, likely by a butane monooxygenase enzyme. c-DCE epoxide transformation was inhibited by both acetylene and c-DCE indicating a monooxygenase enzyme was involved. The epoxide transformation was also stopped when mercuric chloride (HgCl2) was added as a biological inhibitor, further support a biological transformation. To our knowledge this is the first report of the biological transform c-DCE epoxide by a butane-grown culture.
authors.affiliation: Department of Environmental Engineering, Korea University, Jochiwon, Choong-Nam, South Korea.
authors.forename: Y
authors.initials: Y
authors.lastname: Kim
authors.forename: L
authors.initials: L
authors.lastname: Semprini
mesh_terms: D000114:Acetylene / Q000633:toxicity; D001711:Biotransformation / Q000187:drug effects; D002073:Butanes; D002712:Chlorides / Q000378:metabolism / Q000633:toxicity; D004000:Dichloroethylenes / Q000378:metabolism*; D004852:Epoxy Compounds / Q000378:metabolism*; D007700:Kinetics; D013058:Mass Spectrometry; D006899:Mixed Function Oxygenases / Q000378:metabolism; D014861:Washington; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D002073:Butanes; D002712:Chlorides; D004000:Dichloroethylenes; D004852:Epoxy Compounds; D014874:Water Pollutants, Chemical; C046888:butane; D006899:Mixed Function Oxygenases; D000114:Acetylene; C035384:1,2-dichloroethylene