title: Phylogenetic groups, virulence genes and quinolone resistance of integron-bearing Escherichia coli strains isolated from a wastewater treatment plant.
abstract: We investigated phylogenetic affiliation, occurrence of virulence genes and quinolone resistance in 109 integron-containing strains of Escherichia coli isolated from a wastewater treatment plant. Selection for integron-bearing strains caused a shift toward phylogroup D, which was most numerous, followed by A, B1 and B2. Phylogroups D and B2, both of which are reported to include virulent extraintestinal pathotypes, made up 50.5% of all isolates and were present in every stage of wastewater treatment, including final effluent. Diarrheagenic pathotypes made up 21% of the strains. The average virulence factor genes score was low (1.40) and the range was from 0 to 5. Quinolone and fluoroquinolone resistance was observed in 56.0% and 50.4% of the strains, respectively; however, it was not associated with virulence factor score. Although the average virulence factor score was low, 17.4% of strains had three and more virulence genes. They were isolated mostly from raw sewage, but 30% of them were cultured from final effluent. Release of multiresistant integron-bearing E. coli strains with virulence traits into the environment may create potential threat and be of public health concern.
authors.affiliation: Department of Microbiology, Faculty of Biology, A. Mickiewicz University, Ul. Umultowska 89, 61-614, Poznań, Poland. amok@amu.edu.pl
authors.forename: Joanna
authors.initials: J
authors.lastname: Mokracka
authors.forename: Ryszard
authors.initials: R
authors.lastname: Koczura
authors.forename: Lucyna
authors.initials: L
authors.lastname: Jabłońska
authors.forename: Adam
authors.initials: A
authors.lastname: Kaznowski
mesh_terms: D000900:Anti-Bacterial Agents; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D024841:Fluoroquinolones; D032023:Integrons / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D015363:Quinolones / Q000494:pharmacology; D014774:Virulence; D014865:Waste Disposal, Fluid; D014871:Water Microbiology
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D015363:Quinolones