title: Exploring the complex response to linuron of bacterial communities from biopurification systems by means of cultivation-independent methods.
abstract: On-farm biopurification systems (BPSs) treat pesticide-contaminated wastewater at farms through biodegradation and sorption processes. However, information on the microbiota involved in pesticide removal in BPSs is scarce. Here we report on the response of BPS bacterial communities to the herbicide linuron (BPS(+)) compared with the control (BPS(-)) in a microcosm experiment. Both denaturing gradient gel electrophoresis (DGGE) and pyrosequencing of 16S rRNA gene fragments amplified from community DNA indicated shifts in the bacterial community after linuron application. Responding populations belonged to taxa that were previously reported from linuron degrading consortia cultivated from soil (Hyphomicrobiaceae, Comamonadaceae, Micrococcaceae). In addition, numerous taxa with increased relative abundance were identified that were previously not associated with linuron degradation. The relative abundance of IncP-1 korB copies increased in response to linuron application. Amplicon pyrosequencing of IncP-1 trfA genes revealed a high IncP-1 plasmid diversity and suggested that populations carrying IncP-1β plasmids increased in relative abundance. Transferable mercury resistance plasmids were exogenously captured from BPS(+)/BPS(-), and in three transconjugants from BPS(+) the gene hylA was detected. Our data suggest the existence of a multispecies linuron degrading bacterial food web and an involvement of IncP-1 plasmids in the adaptation of bacterial communities to pesticide pollution in BPSs.
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany Civil Engineering Department, Catholic University of Rio de Janeiro, Rua Marquês de São Vicente 225/301-L, Gávea, 22453-900, Rio de Janeiro, RJ, Brazil simonedgs@yahoo.com.br.
authors.forename: Simone
authors.initials: S
authors.lastname: Dealtry
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany.
authors.forename: Eman H
authors.initials: EH
authors.lastname: Nour
authors.affiliation: Section for Microbiology, Department of Biology, University of Copenhagen, Universitetsparken 15, Copenhagen OE, Denmark.
authors.forename: Peter N
authors.initials: PN
authors.lastname: Holmsgaard
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany.
authors.forename: Guo-Chun
authors.initials: GC
authors.lastname: Ding
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany.
authors.forename: Viola
authors.initials: V
authors.lastname: Weichelt
authors.affiliation: Division of Soil and Water Management, KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Dunon
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Heuer
authors.affiliation: Section for Microbiology, Department of Biology, University of Copenhagen, Universitetsparken 15, Copenhagen OE, Denmark Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde Denmark.
authors.forename: Lars H
authors.initials: LH
authors.lastname: Hansen
authors.affiliation: Section for Microbiology, Department of Biology, University of Copenhagen, Universitetsparken 15, Copenhagen OE, Denmark.
authors.forename: Søren J
authors.initials: SJ
authors.lastname: Sørensen
authors.affiliation: Division of Soil and Water Management, KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Springael
authors.affiliation: Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Institute for Epidemiology and Pathogen Diagnostics, 38104 Braunschweig, Germany.
authors.forename: Kornelia
authors.initials: K
authors.lastname: Smalla
mesh_terms: D001673:Biodegradation, Environmental; D042621:Comamonadaceae / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D006540:Herbicides / Q000378:metabolism* / Q000494:pharmacology*; D008044:Linuron / Q000378:metabolism* / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012987:Soil; D012988:Soil Microbiology; D062065:Wastewater / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D006540:Herbicides; D008044:Linuron; D012336:RNA, Ribosomal, 16S; D012987:Soil; D062065:Wastewater
keywords: IncP-1; degradation; linuron; pesticide