Effect of antibiotic resistant factors in effluent of wastewater treatment plant on stream

The antibiotic resistant genes (ARG) and mobile genetic elements (MGE) were investigated with the effluent of wastewater treatment plant (WWTP), and river waters of upstream and downstream in order to elucidate the effect of effluent on antibiotic resistance in a natural river. Total numbers of 134~183 of ARG and MGE were detected and the abundance of ARG and MGE was 0.063~0.422 copies per one of 16S rRNA gene in three water samples. Effluent sample contained the highest amount of the total number and abundance of ARG and MGE whereas total viable cells were observed in the lowest amount among the three samples. This indicated that the genes were originated from cells died during the wastewater treatment process. In addition, the co-relationship of abundance between ARG and MGE suggested that acquired resistance was a prevalent mechanism among the antibiotic-resistant bacteria existing in WWTP.