摘要

       为了全面了解多种消毒方案对饮用水中抗生素耐药性的影响，本研究利用宏基因组学方法揭示了抗生素耐药基因 (ARG) 和细菌群落的变化模式及其关联。在饮用水中共检测到 17 种类型的 297 个 ARG，它们的总相对丰度范围为每个细胞 195.49 ± 24.85 至 626.31 ± 38.61 个 ARG 拷贝。抗菌树脂和紫外线 (AR/UV) 消毒后总 ARG 丰度显着增加，而臭氧和氯 (O3/Cl2) 消毒后总 ARG 丰度显着下降，并在 AR/Cl2 消毒后保持稳定。总体而言，包括bacA、mexT和blaOXA-12在内的18个ARGs，主要隶属于杆菌肽、多药和β-内酰胺，在饮用水中的所有消毒策略中都具有持久性和区分性，它们被认为是代表抗生素的关键ARGs在饮用水消毒过程中具有抵抗力。此外，基于共现网络揭示了 50% 关键 ARG 的可能宿主。在多次消毒过程中，梭杆菌和气单胞菌的丰度变化主要促成了bacA的丰度变化，假单胞菌主要增加了mexT的丰度。这些发现表明细菌群落变化可能是驱动消毒过程中抗生素耐药性变化的关键因素。本研究中提出的抗生素耐药性改变与细菌群落转变之间的强关联可能会加深我们对消毒效果对抗生素耐药性影响的潜在机制的理解，并有助于采取有效措施提高饮用水安全。

       For comprehensive insights into the effects of multiple disinfection regimes on antibiotic resistome in drinking water, this study utilized metagenomic approaches to reveal the changing patterns of antibiotic resistance genes (ARGs) and bacterial community as well as their associations. A total of 297 ARGs within 17 types were detected in the drinking water, and their total relative abundance ranged from 195.49 ± 24.85 to 626.31 ± 38.61 copies of ARGs per cell. The total ARG abundance was significantly increased after the antimicrobial resin and ultraviolet (AR/UV) disinfection while significantly decreased after the ozone and chlorine (O3/Cl2) disinfection and remained stable after AR/Cl2 disinfection. Overall, 18 ARGs including bacA, mexT, and blaOXA-12, mainly affiliated to bacitracin, multidrug, and beta-lactam, were persistent and discriminative during all the disinfection strategies in drinking water, and they were considered as key ARGs that represent the antibiotic resistome during drinking water disinfection. Additionally, possible hosts of 50% key ARGs were revealed based on co-occurrence network. During multiple disinfection processes, the change of Fusobacteriales and Aeromonadaceae in abundance mainly contributed to the abundance shift of bacA, and Pseudomonas mainly increased the abundance of mexT. These findings indicated that bacterial community shift may be the key factor driving the change of antibiotic resistome during disinfection. The strong association between antibiotic resistome alteration and bacterial community shift proposed in this study may enhance our understanding of the underlying mechanism of the disinfection effects on antibiotic resistance and benefit effective measures to improve safety of drinking water.

https://www.sciencedirect.com/science/article/abs/pii/S004313542030258X