title: Discharge of KPC-2 genes from the WWTPs contributed to their enriched abundance in the receiving river.
abstract: At present, very little is known about the persistence and spread pathway of KPC-2 genes in the environment. Our previous study reported the prevalence and persistence of KPC-2 genes in wastewater treatment plants (WWTPs). In the present work, we investigated the occurrence and fate of KPC-2 genes in a WWTP discharge-receiving river and studied the effect of WWTP discharges on the prevalence of KPC-2 genes and host bacteria in the receiving river. It is observed that a considerable level of KPC-2 genes occurred in the receiving river, and a significant increase of blaKPC-2abundance in the downstream following WWTP discharge was observed compared to the upstream. Furthermore, opportunistic pathogens with 100% identical blaKPC-2sequence, like Escherichia coli and Kluyvera georgiana, were isolated from both WWTP and its receiving water, whereas no blaKPC-2carrying bacteria was detected in the upstream. These findings indicated that the treated wastewater discharges have a considerable influence on blaKPC-2levels in the receiving river. Interestingly, there is no correlation between concentrations of antibiotics and blaKPC-2concentrations, demonstrating that the increase of KPC-2 genes in the receiving river is mainly due to WWTP release. This finding is important because it illustrates a significant pathway for KPC-2 gene proliferation to the environment.
authors.affiliation: College of Environmental Science and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin, China.
authors.forename: Fengxia
authors.initials: F
authors.lastname: Yang
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Huang
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin, China.
authors.forename: Linyun
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Environmental Science and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin, China. Electronic address: mao@tju.edu.cn.
authors.forename: Daqing
authors.initials: D
authors.lastname: Mao
authors.affiliation: College of Environmental Science and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin, China. Electronic address: luoy@nankai.edu.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Luo
mesh_terms: D000900:Anti-Bacterial Agents; D001419:Bacteria; D005798:Genes, Bacterial; D045483:Rivers; D062065:Wastewater / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Environmental risk; KPC-2; Receiving river; Wastewater treatment plant