Determination of levels of bacterial contamination in the Aksu River (Kahramanmaraş) and determination of antibiotic and heavy metal resistance in Enterobacteriaceae species

In this research, on the bacteria belonging to Enterobacteriaceae isolated from the Aksu River, the antibiotic, heavy metal resistance, the elimination of their resistance and resistance transfer were examined. A heavy bacterial contamination was determined in the Aksu River. 67 strains Enterobacteriaceae were isolated in the water samples, and among the isolates, E. coli were represented at a rate of 67.2, Klebsiella sp. at a rate of 29.8%, Citrobacter sp. at a rate of 1.5% and Pseudomonas sp. at a rate of 1,5%. Resistance tests against KP, ATM, CRP, CZ, SAM, FOX, IPM, CEF, CFZ, CRO, MER, CTX antibiotics were carried out in the isolated strains, and in 76% of them a multiple antibiotic resistance was determined. The resistance frequency of the isolates was determined for the following heavy metals: Ni, Cd, Cu, and Cr. 94% of the bacteria showed a multiple resistance against these heavy metals. According to the Nitrocephin method, the bacteria were tested for beta-lactamases producing ability and 49.3 % of the isolates were found to be beta-lactamase producing. On the beta-lactamase producing 11 strains, resistance elimination test was carried out by using ethidium bromide and resistance elimination was observed in different rate for the antibiotics, KP, ATM, CRP, CZ, SAM, FOX, IPM, CEF, CFZ, CRO and MER. Conjugation between E.coli and Klebsiella sp were seen in different rates for KP, ATM, CRP, CZ, £AM, FOX, IPM, CEF, CFZ, CRO, and MER antibiotics in the conjugation experiments. By isolating plasmids from conjugates the plasmid DNA were separated in Agarose Gel Electrophoresis but no plasmid determined. These results suggest that releasing of urban and industrial wastewater into surface waters as running waters without treatment process increases the bacterial resistance against antibiotics and heavy metals. Subsequently the infectious diseases, antibiotic resistance and heavy metal resistance are spreaded on large areas. Key Words: Aksu River, Enterobacteriaceae, Resistance, Conjugation