title: Environmental waters as a source of antibiotic-resistant Enterococcus species in Belgrade, Serbia.
abstract: Despite the number of studies on antibiotic-resistant enterococci from Serbian clinical settings, there are no data about environmental contamination with these bacteria. Thus, this study investigated the prevalence of antibiotic-resistant enterococci in Belgrade, Serbia. Enterococcus species collected from ten surface water sites, including a lake, two major river systems, and springs, were tested. Among enterococci, we found single (21.7 %), double (17.4 %), and multiple antibiotic resistance patterns (56.3 %). Vancomycin-resistant strains were not found, indicating that their abundance in Belgrade is tightly linked to clinical settings. The multiple drug-resistant strains Enterococcus faecalis, Enterococcus faecium, and Enterococcus mundtii were frequently detected in the lake during the swimming season and in the rivers near industrial zones. We confirmed the presence of ermB, ermC, ant(6)-Ia, tetM, and tetL and mutations in gyrA genes. The phylogenetic analysis of 16S rRNA gene of E. faecium isolates that harbor esp gene classified them into two groups based on high-bootstraps scores in the tree analysis. Pulsed-field gel electrophoresis analysis of antibiotic-resistant enterococci revealed genomic similarity ranging from 75 to 100 %. This study indicates the importance of anthropogenic impact to the spread of antibiotic-resistant enterococci in environmental waters of Belgrade, Serbia.
authors: Institute of Molecular Genetics and Genetic Engineering (IMGGE), University of Belgrade, Vojvode Stepe 444a, P. O. Box 23, 11010, Belgrade, Serbia, katarinak76@yahoo.com.
authors: Katarina
authors: K
authors: Veljović
authors: Nikola
authors: N
authors: Popović
authors: Amarela Terzić
authors: AT
authors: Vidojević
authors: Maja
authors: M
authors: Tolinački
authors: Sanja
authors: S
authors: Mihajlović
authors: Branko
authors: B
authors: Jovčić
authors: Milan
authors: M
authors: Kojić
mesh_terms: D001483:Base Sequence; D002947:Cities; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D016983:Enterococcus / Q000235:genetics*; D004784:Environmental Monitoring / Q000379:methods / Q000706:statistics & numerical data*; D005798:Genes, Bacterial / Q000235:genetics; D060106:Lakes / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D045483:Rivers / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D055771:Serbia
chemical_list: D012336:RNA, Ribosomal, 16S