Abundance of antibiotic resistance genes in bacteria and bacteriophages isolated from wastewater in Shiraz.

Generally, the high widespread presence of antimicrobial resistance, and the next freeing into aquatic environments which provide a situation for transmission of these genes in water is because of the abuse of the antimicrobial drugs in both medicine and veterinary medicine. In aquatic environment, bacteriophages could have an important role in sharing antimicrobial resistance genes. The purpose of this study was to assess three important antibiotic resistance genes including two β-lactamases (blaTEM, blaSHV) and sul1 gene, referring to resistance to sulfonamides, in both bacteria and phage DNA fractions of wastewater samples, Shiraz, Iran, using polymerase chain reaction. The prevalence of those genes was extremely high and equal to 100% in bacterial DNA, while these rates were lower in phage DNA fractions as 66.66%, 66.66% and 58.33% for blaTEM, blaSHV and sul1, respectively. In conclusion, detection of mentioned genes in bacterial and phage DNA fractions from ambient water is considerable, so the possibility of harbouring and transferring of antibiotic resistance genes by phages needs to be explored in the future. Also, available data is a reputable endorsement that wastewater is a hotspot for these kinds of genes to spread in the environment. Based on our knowledge, this is the first report of blaTEM and bla SHV and sul1 genes in bacterial and phage DNA fractions insulated from urban wastewater and environment in Iran.