Examining Waterways Near UF Campus for Antimicrobial Resistance

The use of clinical antibiotics has greatly increased the scope and severity of naturally occurring antimicrobial resistance (AMR) patterns. Processing of wastewater by wastewater treatment plants (WWTPs) reduces but does not eliminate the concentration of clinical antibiotics present. Bacterial communities residing in aquatic biofilms are more easily able to exchange genes than their planktonic counterparts and thus display a higher rate of AMR. Previous work has indicated the presence of clinical antibiotics and AMR genes in several aquatic systems worldwide. Gainesville, FL has a significant population density and is home to the state’s third-largest hospital as well as a major university; thus, environmental monitoring for AMR genes is a pertinent undertaking. Biofilms were sampled from sites along the Sweetwater Branch Creek upstream and downstream of the GRU Main Street Water Reclamation Facility (WWTP). Colonies were screened for resistance on R2A plates containing ampicillin, methicillin, or vancomycin. After four days, colonies were randomly selected for genetic analysis via polymerase chain reaction (PCR) and gel electrophoresis to detect corresponding antimicrobial resistance genes. Only two colonies of thirty-five were positive for AMR genes: one colony from the downstream site which displayed the ampC gene for ampicillin resistance and one upstream isolate which displayed the vanA gene for vancomycin resistance. The preliminary results of this sampling project indicate only a small amount of resistance present along the Sweetwater Branch Creek, though AMR dynamics may be better illuminated by further analysis.