Cultivation-dependent and cultivation-independent investigation of O-methylated pollutant-producing bacteria in three drinking water treatment plants

Yiran Tang; Zhixuan Wu; Yanfen Zhang; Chuanxuan Wang; Xuelian Ma; Kejia Zhang; Renjie Pan; Yucheng Cao; Xinyan Zhou

doi:10.1016/j.watres.2023.119618

Cultivation-dependent and cultivation-independent investigation of O-methylated pollutant-producing bacteria in three drinking water treatment plants

Water Res. 2023 Mar 1:231:119618. doi: 10.1016/j.watres.2023.119618. Epub 2023 Jan 17.

Authors

Yiran Tang¹, Zhixuan Wu¹, Yanfen Zhang¹, Chuanxuan Wang¹, Xuelian Ma¹, Kejia Zhang², Renjie Pan³, Yucheng Cao¹, Xinyan Zhou⁴

Affiliations

¹ College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China.
² College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang 310058, China.
³ State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
⁴ College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China. Electronic address: zhouxy1993@zafu.edu.cn.

PMID: 36706470
DOI: 10.1016/j.watres.2023.119618

Abstract

O-methylated pollutants (OMPs) are emerging contaminants in drinking water and mainly produced through bacterial O-methylation. However, the information of OMP-producing bacteria (OMPPB) in drinking water treatment plant (DWTP) is largely unknown so far. In this study, the OMPPB in water samples from three DWTPs (XL, JX and NX) were investigated by using cultivation-dependent and cultivation-independent technologies. Four OMPs were detected and their odor and toxicity risks were assessed. Formation potentials (FPs) of 2,4,6-trichloanisole, 2,3,6-trichloanisole, 2,4,6-tribromoanisole, pentachloroanisole and diclofenac methyl ester were determined in water samples and their values shifted significantly among DWTPs. A most probable number (MPN) method was established to quantify OMPPB numbers and the relationships between total haloanisole FPs (HAFPs) (y) and OMPPB numbers (x) in three DWTPs could be described by the following functions: y = 0.496×^0.373 (XL), y = 0.041×^0.465 (JX) and y = 0.218×^0.237 (NX). Several genera like Bacillus, Ralstonia, Brevundimonas, etc. were newly found OMPPB among the cultivable bacteria, and their OMP products were evaluated in terms of quantity and environment risks (odor, toxicity and bioaccumulation). High-throughput sequencing revealed treatment process was the main driving factor to shape the OMPPB community structures and Mantel test showed HAFP profile was significantly influenced by Mycobacterium and Pelomonas. PICURSt2 analysis discovered four phenolic O-methyltransferases (OMTs) and four carboxylic OMTs which might be responsible for OMP formation. Several strategies were recommended to assess risk and control contamination brought by OMPPB in DWTPs.

Keywords: Bacterial community; Drinking water treatment plant; Formation potential; Most probable number; O-methylated pollutant-producing bacteria; O-methyltransferase.

MeSH terms

Bacteria
Drinking Water* / analysis
Environmental Pollutants* / analysis
Esters / analysis
Water Pollutants, Chemical* / chemistry
Water Purification* / methods

Substances

Drinking Water
Environmental Pollutants
Esters
Water Pollutants, Chemical