title: Exploring methane-oxidizing communities for the co-metabolic degradation of organic micropollutants.
abstract: Methane-oxidizing cultures from five different inocula were enriched to be used for co-metabolic degradation of micropollutants. In a first screening, 18 different compounds were tested for degradation with the cultures as well as with four pure methane-oxidizing bacterial (MOB) strains. The tested compounds included pharmaceuticals, chemical additives, pesticides, and their degradation products. All enriched cultures were successful in the degradation of at least four different pollutants, but the compounds degraded most often were sulfamethoxazole (SMX) and benzotriazole (BTZ). Addition of acetylene, a specific methane monooxygenase (MMO) inhibitor, revealed that SMX and BTZ were mainly degraded co-metabolically by the present MOB. The pure MOB cultures exhibited less degradation potential, while SMX and BTZ were also degraded by three of the four tested pure strains. For MOB, copper (Cu(2+)) concentration is often an important factor, as several species have the ability to express a soluble MMO (sMMO) if the Cu(2+) concentration is low. In literature, this enzyme is often described to have a broader compound range for co-metabolic degradation of pollutants, in particular when it comes to aromatic structures. However, this study indicated that co-metabolic degradation of the aromatic compounds SMX and BTZ was possible at high Cu(2+) concentration, most probably catalyzed by pMMO.
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), Department of Biochemical and Microbial Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
authors.forename: Jessica
authors.initials: J
authors.lastname: Benner
authors.forename: Delfien
authors.initials: D
authors.lastname: De Smet
authors.forename: Adrian
authors.initials: A
authors.lastname: Ho
authors.forename: Frederiek-Maarten
authors.initials: FM
authors.lastname: Kerckhof
authors.forename: Lynn
authors.initials: L
authors.lastname: Vanhaecke
authors.forename: Kim
authors.initials: K
authors.lastname: Heylen
authors.forename: Nico
authors.initials: N
authors.lastname: Boon
mesh_terms: D003300:Copper / Q000378:metabolism; D004783:Environmental Microbiology; D004785:Environmental Pollutants / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism; D059013:Microbial Consortia; D009930:Organic Chemicals / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D004785:Environmental Pollutants; D004791:Enzyme Inhibitors; D009930:Organic Chemicals; D003300:Copper