Antibiotic resistance genes of escherıihia coli in coastal marine environment of eastern Black Sea, Turkey

Abstract

Antibiotic resistance and transferable resistance genes were investigated in the bacteria isolated from Mediterranean mussel (Mytilus galloprovincialis) and sea snail (Rapana venosa) collected from the Eastern Black Sea coast of Turkey. Fifty-four Escherichia coli were isolated from Mediterranean mussel and sea snail collected from the coast of Artvin, Rize, Trabzon, and Giresun, Turkey. the multiple antibiotic resistance index was calculated and above the critical limit in the Rize, Trabzon, and Giresun stations. PCR assays were performed to detect sulfonamide (cull, sul2, and sul3), beta-lactam (ampC and b/acrx-Ml), amphenicol (chloramphenicol resistance gene, cmlA, and florfenicol resistance gene, floR), aminoglycoside (aadA), quinolone (qnrS) resistance genes and integrons (Class 1 and Class 2) in all strains and transconjugants. Among the antibiotic resistance genes, ampC was the most common gene followed by blacTx-M1. ampC, blacTx-M1, and cmlA resistance gene was detected in >50% of the isolates. Approximately 44.4% of the total bacteria carried a plasmid; 42% of these plasmid-carrying bacteria could be transferred to recipient strains during conjugation tests. Most of the genes found in donor strains were also detected in plasmid-transferred transconjugant bacteria. These results indicate that the Mediterranean mussel and sea snail could play an important role in antibiotic resistance development and resistance gene dissemination among bacteria.