title: Concentration of facultative pathogenic bacteria and antibiotic resistance genes during sewage treatment and in receiving rivers.
abstract: Whereas the hygienic condition of drinking and bathing water by law must be monitored by culture-based methods, for quantification of microbes and antibiotic resistance in soil or the aquatic environment, often molecular genetic assays are used. For comparison of both methods, knowledge of their correlation is necessary. Therefore the population of total bacteria, Escherichia coli, enterococci and staphylococci during sewage treatment and in receiving river water was compared by agar plating and quantitative polymerase chain reaction (qPCR) assays. In parallel, all samples were investigated for clinically relevant antibiotic resistance genes. Whereas plating and qPCR data for total bacteria correlated well in sewage after primary treatment, qPCR data of river water indicated higher cell numbers for E. coli. It is unknown if these cells are 'only' not growing under standard conditions or if they are dead. Corresponding to the amount of non-culturable cells, the 'breakpoints' for monitoring water quality should be adapted. The abundances of clinically relevant antibiotic resistance genes in river water were in the same order of magnitude or even higher than in treated sewage. For estimation of the health risk it is important to investigate which species carry respective genes and whether these genes are disseminated via gene transfer.
authors: Faculty of Technology, Microbiology-Biotechnology, University of Applied Science Emden/Leer, Constantiaplatz 4, Emden 26723, Germany E-mail: stefanie.hess@hs-emden-leer.de.
authors: Stefanie
authors: S
authors: Heß
authors: Institute for Lake Research, State Institute for the Environment, Measurements and Conservation in Baden-Württemberg, Argenweg 50/1, Langenargen 88085, Germany.
authors: Frauke
authors: F
authors: Lüddeke
authors: Faculty of Technology, Microbiology-Biotechnology, University of Applied Science Emden/Leer, Constantiaplatz 4, Emden 26723, Germany E-mail: stefanie.hess@hs-emden-leer.de.
authors: Claudia
authors: C
authors: Gallert
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification*; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016983:Enterococcus / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification; D005858:Germany; D045483:Rivers / Q000382:microbiology*; D012722:Sewage / Q000382:microbiology*; D040141:Staphylococcaceae / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D012722:Sewage