title: Effects of subinhibitory ciprofloxacin concentrations on the abundance of qnrS and composition of bacterial communities from water supply reservoirs.
abstract: We used a short-term microcosm approach to investigate the influence of two different subinhibitory concentrations of ciprofloxacin (0.01 and 0.1 μg/ml) on both the abundance of a plasmid-mediated quinolone resistance determinant (qnrS) and the structure and composition of bacterial communities from impaired and pristine water supply reservoirs. The results showed that the abundance of the qnrS gene increases in water samples exposed to both subinhibitory concentrations of ciprofloxacin, especially in water samples from La Llosa del Cavall, which represents the pristine system. Subinhibitory ciprofloxacin concentrations also induced changes in bacterial community composition as indicated by the relative abundances of each operational taxonomic unit (OTU) across treatments. Therefore, our findings may be of significant importance because subinhibitory ciprofloxacin concentrations may promote antibiotic resistance and affect bacterial community composition in environmental settings.
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Marti
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Belinda
authors.initials: B
authors.lastname: Huerta
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Rodríguez-Mozaz
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain; Department of Environmental Chemistry, IDAEA-CSIC, C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: Damià
authors.initials: D
authors.lastname: Barceló
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain. Electronic address: jlbalcazar@icra.cat.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Balcázar
authors.affiliation: Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Emili Grahit 101, 17003 Girona, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Marcé
mesh_terms: D002939:Ciprofloxacin / Q000032:analysis* / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial / Q000187:drug effects / Q000235:genetics*; D005798:Genes, Bacterial; D059013:Microbial Consortia / Q000187:drug effects* / Q000235:genetics; D008826:Microbial Sensitivity Tests; D010957:Plasmids; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity; D014881:Water Supply / Q000592:standards
chemical_list: D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D002939:Ciprofloxacin
keywords: Antibiotic resistance genes; Aquatic systems; Bacterial community; Quinolones; Water supply reservoirs