Detection of Beta-Lactamase Variants in Municipal Wastewater and Fresh Water

Abstract

The occurrence and spread of antibiotic-resistant genes (ARGs) are pressing public health problems worldwide. A key factor contributing to the spread of ARGs is lateral gene transfer. Wastewater treatment plants (WWTPs) are measured hot spots of microbial diversity and resistance because they receive polluted wastewater from diverse sources and contain a variety of different environments with dense bacterial loads. Due to the overuse of antibiotics the genetic capacities of microbes have profited. This helps every source of resistance gene and every means of horizontal gene transmission to develop the multiple mechanism of resistance to each antibiotic used clinically, agriculturally, or by any other medium. In wastewater treatment plants, where gastrointestinal wastes from city residents co-mingle, the probability for lateral gene transfer events is greatly increased. In this study, we use PCR technique to detect four beta-lactamase loci to assess the prevalence of ARGs. Wastewater samples from municipal plant at different stages of treatment as well as water samples from the river upstream and downstream from the release site were collected, followed by total DNA extraction and purification. These were then used as templates in PCR-based detection of beta-lactamase (bla) resistance loci. Our results showed the presence of four loci (blaKPC, blaTEM, blaSHV, blaAMPC) in influx, secondary treatment wastewater but not in the efflux, nor in the river water samples. Up to now we can say there is no detectable levels of ARGs in WWTP effluent samples, upstream and the downstream rivers. These data are vital in understanding the role of WWTPs in contributing to the spread of antibiotic resistance in the environment.

Date of Award	2019
Original language	American English
Awarding Institution	Eastern Illinois University
Supervisor	Billy Hung (Supervisor)