15 research outputs found
Differentiation between closely related lentil (Lens culinaris Medik.) cultivars using DNA markers
Extended spectrum beta-lactamases in Escherichia coli from municipal wastewater
Introduction and objective
Over the past decades, awareness of the environmental load of resistant organisms has increased. The presented paper focuses on antibiotic resistance and detection of resistance genes in environmental E. coli and on the evaluation of biofilm formation in ESBLs (extended spectrum beta-lactamase) producing E. coli isolated from an urban wastewater treatment plant.
Material and Methods
Wastewater samples and artificially added polystyrene pellets were used as the source for E. coli isolation. Minimal inhibitory concentrations of 19 antibiotics were determined according to CLSI (2013). Biofilm formation was investigated by crystal violet or resazurin methods. CTX-M, carbapenemases, qnrS, mobile elements and virulence factors were determined by PCR. Clonal relatedness of strains was detected by principal component analysis by a Maldi biotyper.
Results
ESBL phenotype was detected in 26% of environmental strains. CTX-M, CMY-2 and qnrS genes of antibiotic resistance were detected. IMP gene together with integron 1 in one ertapenem resistant E. coli was also recorded. There was no evident correlation between antibiotic resistance, virulence and biofilm production.
Conclusions
Conclusions. The results showed that the wastewater is a source of ESBLs, carbapenemases and plasmid fluoroquinolone resistance. Strains with biofilm production, antibiotic resistance of CTX-M group, CMY-2, qnrS genes and virulence factors present a potential environmental health risk
Antibiotic resistance of Escherichia coli isolated from a poultry slaughterhouse
The aim of the study was to investigate the antibiotic resistant E. coli strains isolated from bioaerosols and surface swabs in
a slaughterhouse as a possible source of poultry meat contamination. The highest air coliforms contamination was during
shackling, killing and evisceration of poultry. The strains showed resistance to ampicillin (89%), ceftiofur (62%) and cefquinome
(22%), while resistance to ampicillin with sulbactam was only 6%. Resistance to streptomycin and gentamicin was detected
in 43% vs. 14% isolates; to tetracycline 33%; to chloramphenicol and florfenicol in 10% vs. 18% isolates; to cotrimoxazol in
35% isolates; to enrofloxacin in 43 % isolates. The higher MIC of ceftazidime (3.6 mg.l-1) and ceftriaxon (5.2 mg.l-1) revealed
the presence of ESBLs in 43% of isolates. From 19 selected phenotypically ESBL positive strains, 16 consisted of CMY-2 genes,
while CTX-M genes were not detected by PCR. Maldi tof analysis of selected E. coli showed a clear clonal relatedness of
environmental strains from various withdrawals