摘要
      在人类环境中经常使用消毒剂来控制和预防微生物疾病的传播，在当前的新冠肺炎危机期间尤其如此。然而，目前尚不清楚污水处理厂消毒剂负荷的增加是否有助于抗生素抗性基因（ARGs）在污水污泥微生物群中的传播。在这里，我们通过高通量定量PCR和Illumina测序研究了广泛使用的消毒剂苯扎氯铵（BACs）对污水污泥中ARGs谱和微生物群落结构的影响。在所有污水污泥样品中共检测到147种独特的ARGs和39种可移动遗传元素（MGE）。我们的研究结果表明，暴露于环境相关浓度的BACs消毒剂显著促进了污泥微生物群中ARG的多样性和绝对丰度，表明BACs消毒剂对ARG的共同选择。与对照相比，ARGs丰度的富集度从2.15倍到3.63倍不等。此外，BACs暴露显著改变了细菌和原生生物群落，导致污泥微生物群的微生态失调。Mantel检验和Procrustes分析证实，在BACs处理下，细菌群落与ARGs谱显著相关。结构方程模型解释了83.8%的ARGs总变异，并进一步说明，在BACs暴露下，MGE的绝对丰度对ARGs绝对丰度的变化的影响比微生物群落更大，这表明BACs可能通过增强ARGs在污泥微生物群中的水平基因转移来促进抗生素耐药性。总的来说，我们的研究结果为在疫情期间通过使用消毒剂来扩散抗生素耐药性提供了新的见解，并强调了最大限度地减少消毒剂向非目标环境中的环境释放以对抗抗生素耐药性的必要性。
Abstract
Disinfectants are routinely used in human environments to control and prevent the transmission of microbial disease, and this is particularly true during the current COVID-19 crisis. However, it remains unclear whether the increased disinfectant loadings to wastewater treatment plants facilitate the dissemination of antibiotic resistance genes (ARGs) in sewage sludge microbiomes. Here, we investigated the impacts of benzalkonium chlorides (BACs), widely used disinfectants, on ARGs profiles and microbial community structures in sewage sludge by using high-throughput quantitative PCR and Illumina sequencing. A total of 147 unique ARGs and 39 mobile genetic elements (MGEs) were detected in all sewage sludge samples. Our results show that exposure to BACs disinfectants at environmentally relevant concentrations significantly promotes both the diversity and absolute abundance of ARGs in sludge microbiomes, indicating the co-selection of ARGs by BACs disinfectants. The enrichment of ARGs abundance varied from 2.15-fold to 3.63-fold compared to controls. In addition, BACs exposure significantly alters bacterial and protistan communities, resulting in dysbiosis of the sludge microbiota. The Mantel test and Procrustes analysis confirm that bacterial communities are significantly correlated with ARGs profiles under BACs treatments. The structural equation model explains 83.8 % of the total ARGs variation and further illustrates that the absolute abundance of MGEs exerts greater impacts on the variation of absolute abundance of ARGs than microbial communities under BACs exposure, suggesting BACs may promote antibiotic resistance by enhancing the horizontal gene transfer of ARGs across sludge microbiomes. Collectively, our results provide new insights into the proliferation of antibiotic resistance through disinfectant usage during the pandemic and highlight the necessity to minimize the environmental release of disinfectants into the non-target environment for combating antibiotic resistance.

https://www.sciencedirect.com/science/article/pii/S0048969723001420