摘要

饮用水中抗生素抗性基因（ARGs）的污染可能对人类健康构成直接威胁。本研究应用高通量qPCR和测序来研究使用生物活性炭进行饮用水深度处理过程中ARG和细菌群落的动态变化。观察到ARGs的促进，并且在BAC治疗后ARG的标准化拷贝数显着增加，将检测到的ARG的数量从84增加到159.在BAC中鉴定出29个ARG作为影响生物膜的来源，并且它们持续存在氯化。细菌群落的转移主要影响抵抗组织的变化。厚壁菌，蓝藻与持久性ARG有关，主要在BAC生物膜中。同时，Acyl-Homoserine Lactones（AHLs），群体感应分子和产生AHL的细菌被确定为了解ARG的促进。产生分离的AHL的细菌属于Proteobacteria，Firmicutes和Bacteroidetes phyla。六个可检测的AHL对基因组交配系统中基于质粒的水平基因转移有影响，表明ARG的动态受到生物膜中特定细菌之间的群体感应的强烈影响。这些结果为BAC生物膜中抗生素抵抗组织促进的机制提供了新的见解。

The contamination of antibiotic resistance genes (ARGs) in drinking water may pose a direct threat to human health. This study applied high-throughput qPCR and sequencing to investigate the dynamics of ARGs and bacterial communities during the advanced treatment of drinking water using biological activated carbon. The promotion of ARGs was observed, and the normalized copy number of ARGs increased significantly after BAC treatment, raising the number of detected ARGs from 84 to 159. Twenty-nine ARGs were identified as biofilm-influencing sources in the BAC, and they persisted after chlorination. The shift of bacterial communities primarily had effects on the changes in resistome. Firmicutes, Cyanobacteria were related to persistent ARGs mostly in the BAC biofilm. Meanwhile, the Acyl-Homoserine Lactones (AHLs), quorum sensing molecules, and bacteria that produced AHLs were identified to understand the promotion of ARGs. The isolated AHL-producing bacteria belonged to the Proteobacteria, Firmicutes and Bacteroidetes phyla. Six detectable AHLs had an influence on plasmid-based horizontal gene transfer in the intragenus mating systems, indicating that the dynamics of ARGs were strongly affected by quorum sensing between specific bacteria in the biofilm. These results provide new insight into the mechanism of antibiotic resistome promotion in BAC biofilms.

https://www.sciencedirect.com/science/article/pii/S0048969717320703