Occurrence of super antibiotic resistance genes in the downstream of the Yangtze River in China: Prevalence and antibiotic resistance profiles

Ruo-Nan Wang; Yuan Zhang; Zhen-Hua Cao; Xin-Yu Wang; Ben Ma; Wen-Bin Wu; Nan Hu; Zheng-Yang Huo; Qing-Bin Yuan

doi:10.1016/j.scitotenv.2018.10.111

Occurrence of super antibiotic resistance genes in the downstream of the Yangtze River in China: Prevalence and antibiotic resistance profiles

Sci Total Environ. 2019 Feb 15;651(Pt 2):1946-1957. doi: 10.1016/j.scitotenv.2018.10.111. Epub 2018 Oct 9.

Authors

Ruo-Nan Wang¹, Yuan Zhang¹, Zhen-Hua Cao¹, Xin-Yu Wang¹, Ben Ma¹, Wen-Bin Wu¹, Nan Hu², Zheng-Yang Huo³, Qing-Bin Yuan⁴

Affiliations

¹ College of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, PR China.
² College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China.
³ Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China.
⁴ College of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, PR China. Electronic address: yuanqb@njtech.edu.cn.

PMID: 30321718
DOI: 10.1016/j.scitotenv.2018.10.111

Abstract

The super antibiotic resistance genes (SARGs) demonstrate more severe threats than other antibiotic resistance genes while have not received enough attention in the environment. The study explored the prevalence and the antibiotic tolerance profiles of two typical SARGs, MCR-1 and NDM-1, and their hosting bacteria in the downstream of the Yangtze River and the nearby wastewater treatment plant (WWTP) and drinking water treatment plant (DWTP). Results indicated that MCR-1 and NDM-1 were prevalent in the influent and biological units of the WWTP. Their hosting bacteria were effectively removed, but 2.49 × 10⁸ copies/L MCR-1 and 7.00 × 10⁶ copies/L NDM-1 were still persistent in the effluent. In the Yangtze River, MCR-1 and NDM-1 were detected with higher abundance and antibiotic tolerance than the WWTP effluent and were significantly affected by nearby water contamination and human activities. In the DWTP, MCR-1 and NDM-1 were detected with average values 5.56 × 10⁷ copies/L and 2.14 × 10⁵ copies/L in the influent. Their hosting bacteria were undetectable in the effluent, but the two SARGs were still persistent with 1.39 × 10⁷ copies/L and 6.29 × 10⁴ copies/L, and were greatly enriched in the sludge. Molecular ecological networks demonstrated wide hosting relationships between MCR-1/NDM-1 and bacteria community in the DWTP. Redundancy analysis found that MCR-1 positively correlated with COD and NH₃-N, while negatively correlated with turbidity. Additionally, MCR-1 hosting bacteria positively correlated with NO₃^--N and negatively correlated with COD and NH₃-N. NDM-1 positively correlated with turbidity and NDM-1 hosting bacteria positively correlated with COD and NO₂^--N. The study demonstrated that the WWTP could not effectively remove SARGs with high amount of them being discharged into the Yangtze River. Then they were transported into the DWTP and the persistent SARGs in the effluent would probably be transferred into human, thus imposing great threats on public health.

Keywords: Abundance; Antibiotic resistance profiles; Bacterial community; MCR-1; NDM-1; The Yangtze River.

MeSH terms

Anti-Bacterial Agents / pharmacology
Bacteria / genetics
Bacteria / isolation & purification*
Bacterial Proteins / analysis*
China
Drug Resistance, Microbial / genetics*
Rivers / microbiology*
Waste Disposal, Fluid
Wastewater / microbiology*
Water Purification
beta-Lactamases / analysis

Substances

Anti-Bacterial Agents
Bacterial Proteins
Waste Water
beta-Lactamases
beta-lactamase NDM-1