Wastewaters belong among the most important sources of environmental pollution, including antibiotic-resistant bacteria. The aim of the study was to evaluate treated wastewaters as a possible transmission pathway for bacterial colonisation of gulls occupying the receiving river. A collection of antibiotic-resistant Escherichia coli originating both from treated municipal wastewaters discharged to the river Svratka (Czech Republic) and nestlings of Black-headed Gull (Chroicocephalus ridibundus) living 35 km downstream of the outlet was obtained using selective cultivation. Isolates were further characterised by various phenotyping and genotyping methods. From a total of 670 E. coli isolates (450 from effluents, 220 from gulls), 86 isolates (41 from effluents, 45 from gulls) showed identical antibiotic resistance phenotype and genotype and were further analysed for clonal relatedness using pulsed-field gel electrophoresis (PFGE). Despite the overall high diversity of the isolates, 21 isolates from both sources showed similar PFGE profiles. Isolates belonging to epidemiologically important sequence types (ST131, 15 isolates; ST23, three isolates) were subjected to whole-genome sequencing. Subsequent phylogenetic analysis did not reveal any close clonal relationship between the isolates from the effluents and gulls' nestlings with the closest strains showing 90 SNPs difference. Although our study did not provide direct evidence of transmission of antibiotic-resistant E. coli to wild gulls via treated wastewaters, we observed gull chicks as carriers of diverse multi-resistant E. coli, including high-risk clones, posing risk of further bacterial contamination of the surrounding environment.

• Keywords
• Enterobacterales, Environment, Whole-genome sequencing, Wild birds,
• Publication type
• Journal Article MeSH

Escherichia coli sequence type 131 (ST131) is currently one of the leading causes of multidrug-resistant extraintestinal infections globally. Here, we analyzed the phenotypic and genotypic characteristics of 169 ST131 isolates from various sources (wildlife, wastewater, companion animals, community, and hospitals) to determine whether wildlife and the environment share similar strains with humans, supporting transmission of ST131 between different ecological niches. Susceptibility to 32 antimicrobials was tested by disc diffusion and broth microdilution. Antibiotic resistance genes, integrons, plasmid replicons, 52 virulence genes, and fimH-based subtypes were detected by PCR and DNA sequencing. Genomic relatedness was determined by pulsed-field gel electrophoresis (PFGE). The genetic context and plasmid versus chromosomal location of extended-spectrum beta-lactamase and AmpC beta-lactamase genes was determined by PCR and probe hybridization, respectively. The 169 ST131 study isolates segregated predominantly into blaCTX-M-15H30Rx (60%) and blaCTX-M-27H30R1 (25%) subclones. Within each subclone, isolates from different source groups were categorized into distinct PFGE clusters; genotypic characteristics were fairly well conserved within each major PFGE cluster. Irrespective of source, the blaCTX-M-15H30Rx isolates typically exhibited virotype A (89%), an F2:A1:B- replicon (84%), and a 1.7-kb class 1 integron (92%) and had diverse structures upstream of the blaCTX-M region. In contrast, the blaCTX-M-27H30R1 isolates typically exhibited virotype C (86%), an F1:A2:B20 replicon (76%), and a conserved IS26-ΔISEcp1-blaCTX-M-like structure. Despite considerable overall genetic diversity, our data demonstrate significant commonality between E. coli ST131 isolates from diverse environments, supporting transmission between different sources, including humans, environment, and wildlife.

• Keywords
• ESBL, Escherichia coli ST131, environment, nosocomial and community-acquired infections, virulence, wildlife,
• MeSH
• Anti-Bacterial Agents pharmacology   MeSH
• beta-Lactamases genetics   MeSH
• Escherichia coli drug effects   genetics   MeSH
• Escherichia coli Infections genetics   microbiology   MeSH
• Community-Acquired Infections genetics   microbiology   MeSH
• Humans MeSH
• Drug Resistance, Multiple, Bacterial genetics   MeSH
• Plasmids genetics   MeSH
• Escherichia coli Proteins genetics   MeSH
• Electrophoresis, Gel, Pulsed-Field MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Names of Substances
• Anti-Bacterial Agents MeSH
• beta-Lactamases MeSH
• Escherichia coli Proteins MeSH

Escherichia coli is a common commensal bacterial species of humans and animals that may become a troublesome pathogen causing serious diseases. The aim of this study was to characterize the quinolone resistance phenotypes and genotypes in E. coli isolates of different origin from one area of the Czech Republic. E. coli isolates were obtained from hospitalized patients and outpatients, chicken farms, retailed turkeys, rooks wintering in the area, and wastewaters. Susceptibility of the isolates grown on the MacConkey agar with ciprofloxacin (0.05 mg/L) to 23 antimicrobial agents was determined. The presence of plasmid-mediated quinolone resistance (PMQR) and ESBL genes was tested by PCR and sequencing. Specific mutations in gyrA, gyrB, parC, and parE were also examined. Multilocus sequence typing and pulsed-field gel electrophoresis were performed to assess the clonal relationship. In total, 1050 E. coli isolates were obtained, including 303 isolates from humans, 156 from chickens, 105 from turkeys, 114 from the rooks, and 372 from wastewater samples. PMQR genes were detected in 262 (25%) isolates. The highest occurrence was observed in isolates from retailed turkey (49% of the isolates were positive) and inpatients (32%). The qnrS1 gene was the most common PMQR determinant identified in 146 (56%) followed by aac(6')-Ib-cr in 77 (29%), qnrB19 in 41 (16%), and qnrB1 in 9 (3%) isolates. All isolates with high level of ciprofloxacin resistance (>32 mg/L) carried double or triple mutations in gyrA combined with single or double mutations in parC. The most frequently identified substitutions were Ser(83)Leu; Asp(87)Asn in GyrA, together with Ser(80)Ile, or Glu(84)Val in ParC. Majority of these isolates showed resistance to beta-lactams and multiresistance phenotype was found in 95% isolates. Forty-eight different sequence types among 144 isolates analyzed were found, including five major clones ST131 (26), ST355 (19), ST48 (13), ST95 (10), and ST10 (5). No isolates sharing 100% relatedness and originating from different areas were identified. In conclusion, our study identified PMQR genes in E. coli isolates in all areas studied, including highly virulent multiresistant clones such as ST131 producing CTX-M-15 beta-lactamases.

• Keywords
• Escherichia coli, MLST, PFGE, animals, human, quinolone resistance, wastewater,
• Publication type
• Journal Article MeSH

Extended-spectrum-beta-lactamase (ESBL)-producing, AmpC beta-lactamase-producing, and plasmid-mediated quinolone resistance (PMQR) gene-positive strains of Escherichia coli were investigated in wintering rooks (Corvus frugilegus) from eight European countries. Fecal samples (n = 1,073) from rooks wintering in the Czech Republic, France, Germany, Italy, Poland, Serbia, Spain, and Switzerland were examined. Resistant isolates obtained from selective cultivation were screened for ESBL, AmpC, and PMQR genes by PCR and sequencing. Pulsed-field gel electrophoresis and multilocus sequence typing were performed to reveal their clonal relatedness. In total, from the 1,073 samples, 152 (14%) cefotaxime-resistant E. coli isolates and 355 (33%) E. coli isolates with reduced susceptibility to ciprofloxacin were found. Eighty-two (54%) of these cefotaxime-resistant E. coli isolates carried the following ESBL genes: blaCTX-M-1 (n = 39 isolates), blaCTX-M-15 (n = 25), blaCTX-M-24 (n = 4), blaTEM-52 (n = 4), blaCTX-M-14 (n = 2), blaCTX-M-55 (n = 2), blaSHV-12 (n = 2), blaCTX-M-8 (n = 1), blaCTX-M-25 (n = 1), blaCTX-M-28 (n = 1), and an unspecified gene (n = 1). Forty-seven (31%) cefotaxime-resistant E. coli isolates carried the blaCMY-2 AmpC beta-lactamase gene. Sixty-two (17%) of the E. coli isolates with reduced susceptibility to ciprofloxacin were positive for the PMQR genes qnrS1 (n = 54), qnrB19 (n = 4), qnrS1 and qnrB19 (n = 2), qnrS2 (n = 1), and aac(6')-Ib-cr (n = 1). Eleven isolates from the Czech Republic (n = 8) and Serbia (n = 3) were identified to be CTX-M-15-producing E. coli clone B2-O25b-ST131 isolates. Ninety-one different sequence types (STs) among 191 ESBL-producing, AmpC-producing, and PMQR gene-positive E. coli isolates were determined, with ST58 (n = 15), ST10 (n = 14), and ST131 (n = 12) predominating. The widespread occurrence of highly diverse ESBL- and AmpC-producing and PMQR gene-positive E. coli isolates, including the clinically important multiresistant ST69, ST95, ST117, ST131, and ST405 clones, was demonstrated in rooks wintering in various European countries.

• MeSH
• Anti-Bacterial Agents pharmacology   MeSH
• Genes, Bacterial MeSH
• Drug Resistance, Bacterial * MeSH
• Cephalosporins pharmacology   MeSH
• Escherichia coli classification   drug effects   genetics   isolation & purification   MeSH
• Fluoroquinolones pharmacology   MeSH
• Genotype MeSH
• Multilocus Sequence Typing MeSH
• Plasmids MeSH
• Polymerase Chain Reaction MeSH
• Electrophoresis, Gel, Pulsed-Field MeSH
• Crows microbiology   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Europe MeSH
• Names of Substances
• Anti-Bacterial Agents MeSH
• Cephalosporins MeSH
• Fluoroquinolones MeSH

Resistance in Escherichia coli isolates colonizing gastrointestinal tracts of dogs, cats, and their owners in Northern Kenya was investigated with an emphasis on extended-spectrum beta-lactamases (ESBLs). Totals of 47 (22%, n = 216), 2 (4%, n = 50), and 4 (17%, n = 23) CTX-M-15-producing E. coli isolates were obtained from dogs, cats, and humans, respectively. CTX-M-15-producing E. coli isolates with identical PFGE profiles were detected in animals and humans living in the same area.

• MeSH
• beta-Lactamases genetics   metabolism   MeSH
• Cephalosporins pharmacology   MeSH
• Quinolones pharmacology   MeSH
• Escherichia coli drug effects   genetics   MeSH
• Cats MeSH
• Humans MeSH
• Drug Resistance, Multiple, Bacterial genetics   MeSH
• Plasmids genetics   MeSH
• Dogs MeSH
• Animals MeSH
• Check Tag
• Cats MeSH
• Humans MeSH
• Dogs MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Kenya MeSH
• Names of Substances
• beta-Lactamases MeSH
• Cephalosporins MeSH
• Quinolones MeSH