Fate, mobility, and pathogenicity of drinking water treatment plant resistomes deciphered by metagenomic assembly and network analyses

Qingqing Zhao; Huan He; Kuo Gao; Tian Li; Bingzhi Dong

doi:10.1016/j.scitotenv.2021.150095

Fate, mobility, and pathogenicity of drinking water treatment plant resistomes deciphered by metagenomic assembly and network analyses

Sci Total Environ. 2022 Jan 15:804:150095. doi: 10.1016/j.scitotenv.2021.150095. Epub 2021 Sep 4.

Authors

Qingqing Zhao¹, Huan He², Kuo Gao¹, Tian Li³, Bingzhi Dong⁴

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
² Department of Civil, Environmental, and Geo-Engineering, University of Minnesota - Twin Cities, 500 Pillsbury Dr. SE, Minneapolis, MN 55445, United States. Electronic address: heh@umn.edu.
³ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; International Joint Research Center for Sustainable Urban Water System, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: litian001@tongji.edu.cn.
⁴ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; International Joint Research Center for Sustainable Urban Water System, Tongji University, 1239 Siping Road, Shanghai 200092, China.

PMID: 34509829
DOI: 10.1016/j.scitotenv.2021.150095

Abstract

Antibiotic resistance genes (ARGs) have been regarded as emerging environmental contaminants. The profile of resistome (collection of all ARGs) in drinking water and its fate during drinking water treatment remain unclear. This study applied metagenomic assembly combined with network analysis to decipher the profile, mobility, host, and pathogenicity of resistomes in two full-scale drinking water treatment plants (DWTPs), each applying conventional treatment and advanced treatment of ozonation followed by biological activated carbon filtration. In source waters and effluents of each treatment process collected from both DWTPs, 215 ARGs belonging to 20 types were detected with total concentration ranging from 6.30 ± 1.83 to 5.20 ± 0.26 × 10⁴ copies/mL. Both the conventional and advanced DWTPs were revealed to effectively reduce the concentration of total ARGs, with the average removal efficiency of 3.61-log₁₀ and 2.21-log₁₀, respectively. Multiple statistical analyses (including network analysis) indicated drinking water resistome correlated tightly with mobile gene elements (MGEs) and bacterial community, with the latter acting as the premier driver of resistome alteration in DWTPs. Further analysis of ARG-carrying contigs (ACCs) assembled from drinking water metagenomes (i) tracked down potential bacterial hosts of ARGs (e.g., Proteobacteria phylum as the major pool of resistome), (ii) provided co-localization information of ARGs and MGEs (e.g., MacB-E7196 plasmid1), and (iii) identified ARG-carrying human pathogens (e.g., Enterococcus faecium and Ralstonia pickettii). This work firstly determined the concentration, mobility incidence, and pathogenicity incidence of DWTP resistomes, based on which the actual health risk regarding antibiotic resistance could be quantitatively assessed in further study, providing a useful direction for decision-making concerning the risk control of ARGs in DWTPs.

Keywords: Antibiotic resistance genes (ARGs); Bacterial community; Drinking water treatment plants (DWTPs); Mobility; Pathogenicity.

MeSH terms

Anti-Bacterial Agents / analysis
Drinking Water*
Genes, Bacterial
Humans
Metagenome*
Metagenomics
Virulence

Substances

Anti-Bacterial Agents
Drinking Water