摘要
      饮用水处理过程和分布都会导致抗生素耐药性的变异，但整个饮用水供应系统（DWSS）中抗生素耐药性的变化与季节性相结合仍然未知。在这项研究中，微生物群落、抗生素抗性组、与抗生素抗性基因（ARG）和ARG宿主共存的移动遗传元件（MGE）将沿着DWSS进行为期四个季节的宏基因组组装。多药和杆菌肽ARGs是DWSS中占主导地位的ARGs。整合酶、质粒、重组酶和转座酶是与ARGs共存的主要MGE。过滤和消毒处理可以改变ARG的相对丰度，主要是通过改变ARG宿主（Limnohabitans和Polynucleobacter）的丰度，这受到水总有机碳（TOC）含量的影响。当TOC相对较高时，过滤可以通过促进抗生素耐药性细菌（ARB）增殖ARGs，但二氧化氯可以通过杀死ARB降低ARGs。当TOC相对较低时，过滤通过减少ARB在控制ARG方面发挥了重要作用。消毒对ARGs的刺激作用存在于更贫营养的环境中。分布可以通过增加与ARG共存的MGE和使ARG宿主多样化，在更高的温度下富集ARG。在温暖的季节，与ARGs共存的MGE在消毒水中变得更加丰富和多样化。微生物群落是决定DWSS抗生素耐药性的最重要因素。这些发现扩展了关于水处理过程和管道分布如何以及为什么在不同季节形成饮用水抗生素耐药性的知识。
Abstract
Both drinking water treatment processes and distribution can lead to antibiotic resistome variation, yet the variation of antibiotic resistome in the whole drinking water supply system (DWSS) combined with seasonality remains unknown. In this study, microbial community, antibiotic resistome, mobile genetic elements (MGEs) co-existing with antibiotic resistance genes (ARGs) and ARG hosts would be explored along a DWSS for four seasons with metagenome assembly. Multidrug and bacitracin ARGs were dominant ARGs in DWSS. Integrase, plasmids, recombinase and transposase were major MGEs co-existing with ARGs. Filtration and disinfection treatments could alter the ARG relative abundance, mainly via changing the abundance of ARG hosts (Limnohabitans and Polynucleobacter), which was influenced by water total organic carbon (TOC) content. When TOC was relatively high, filtration could proliferate ARGs via promoting antibiotic resistance bacteria (ARB) but chlorine dioxide could decrease ARGs via killing ARB. Filtration played an important role in controlling ARGs by reducing ARB when TOC was relatively low. The stimulation effect of disinfection on ARGs existed in more oligotrophic environment. Distribution could enrich ARGs in higher temperature by increasing MGEs co-occurring with ARGs and diversifying ARG hosts. MGEs co-occurring with ARGs became more abundant and diverse in disinfected water in warmer seasons. Microbial community was the most important factor determining the antibiotic resistome along a DWSS. These findings extend the knowledge about how and why water treatment processes and pipe distribution shape drinking water antibiotic resistome in different seasons.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722079906