Science of the Total Environment

0048-9697

765

SCIE

[논문]Metagenomic exploration of antibiotic resistome in treated wastewater effluents and their receiving water

Shahbaz Raza, Tatsuya Unno

Hyejun Jo

Jungman Kim (김정만)

Hanseob Shin

Hor-Gil Hur

Environmental dissemination of antimicrobial resistance is a global health problem. Antimicrobial-resistant bacteria
and antibiotic-resistant genes (ARGs) are constantly released into the environment through effluents (EFs)
from wastewater treatment plants (WWTPs). Thus, requiring a better understanding of the selection and fate of
ARGs in wastewater treatment processes. Therefore, we investigated the impacts of urban WWTP EFs on receiving
water in the context of their resistomes and mobilomes. We used a HiSeq-based short read metagenomic approach
to address the dynamics and diversity of ARGs inWWTP EF as well as the upstream (UP) and downstream
(DN) river waters, followed by an investigation of plasmid-mediated ARGs. The abundance of ARGs at each site
varied from 7.2 × 10−2 to 7.4 × 10−1 ARG copies per 16S rRNA gene copy, and EF samples showed the highest
abundance, followed by DN and UP water samples. ARG diversity ranged from 121 to 686 types per site, and
EF had the most diverse ARGs. Commonly identified ARGs in the EF and DN samples were clinically important
and were absent in UP samples. The abundance of ARGs, mobile genetic elements (MGEs), and plasmid contigs
found only in EF and DN were positively correlated with each other, indicating the importance of mobilomes
in the dissemination of ARGs in the environment. Moreover, the proportions of plasmid-mediated ARGs was
highest in the EF samples, followed by the DN and UP samples. These findings suggest that WWTP EF may act
as a driving factor shaping the resistomes and mobilomes of receiving waters. In particular, a higher abundance
of plasmid-mediated ARGs in WWTP EF suggests higher transmissibility in the DN environment.

2021-04-15

10.1016/j.scitotenv.2020.142755