Repozytorium publikacji - Politechnika Gdańska

The aim of this preliminary study was to assess the occurrence and molecular diversity of tetracycline and ampicillin resistance genes carried by Escherichia coli present in surface water. Bacterial strains were isolated from two watercourses (the Reda River and the Oliwski Stream) that influence the quality of coastal waters in the Gdańsk Bay (Northern Poland) by direct discharge. The bacterial drug susceptibility, tested against 19 antimicrobial agents (aminoglycosides, carbapenems, cephalosporines, folate antagonists, fluoroquinolones, monobactam, penicillins, penicillins/b-lactamase inhibitors, and tetracycline), indicated that resistance to ampicillin (AM) and tetracycline (TE) was the most frequent. Thus this analysis was followed by PCR assays to identify the TE and AM resistance determinants among the isolates using primers specific for the tetA-C genes (3 primer pairs in total) and β-lactamase genes (blaTEM, blaOXA-B and blaSHV, 3 pairs in total). The role of plasmids in the horizontal gene transfer of these resistance determinants was also attempted. Plasmid DNA was extracted from the bacteria using alkaline lysis method and the material was used for transformation of Escherichia coli DH5α cells. In the PCR assays 23 E. coli isolates were used (15 were TE-resistant and 20 were AM-resistant, some strains showed double resistance). TetR genes were detected in 60% of the TE-resistant E. coli strains, with predominance of tetB. The amplification of tetC gene was not observed. The only b-lactamase gene detected was blaTEM. Transformation of the E. coli DH5α recipient cells with plasmid DNA extracted from surface water isolates resulted in the transfer of resistance from 75% of AM-resistant and 20% of TE-resistant E. coli. This indicates that E. coli may be an important environmental source for horizontal transfer of resistance genes.

Autorzy

• prof. dr hab. inż. Aneta Łuczkiewicz link otwiera się w nowej karcie ,
• Ewa Kotlarska,
• dr hab. Katarzyna Jankowska link otwiera się w nowej karcie ,
• Borys Wróbel link otwiera się w nowej karcie ,
• prof. dr hab. inż. Krystyna Olańczuk-Neyman link otwiera się w nowej karcie