摘要

       为了更好地了解抗生素抗性基因 (ARGs) 在不同环境基质中的潜在基因通讯和传播，探索了河流表层水和沉积物之间 ARG 谱的差异。应用宏基因组分析研究了从北江及其河源受人类影响严重的集水区收集的水和沉积物样品中的综合 ARG 谱。共鉴定了属于 18 个 ARG 类型的 135 个 ARG 亚型。一般来说，地表水中的 ARGs 比沉积物中的 ARGs 更加多样化和丰富。地表水和沉积物样品中的 ARG 剖面彼此不同，但一些 ARG 由地表水和沉积物共享。结果表明，多药和杆菌肽抗性基因是地表水（0.30、0.17 拷贝/细胞）和沉积物（0.19、0.15 拷贝/细胞）中的主要 ARG 类型。水和沉积物样品共有 73 个 ARG 亚型，占总检测到的 ARG 丰度的 90% 以上。大多数共享的 ARG 对临床相关的抗生素具有抗性。此外，在地表水和沉积物中发现了 ARGs 与 21 个共享属或移动遗传元件 (MGEs)（质粒和整合子）之间的显着相关性，表明属或 MGEs 在塑造 ARGs 剖面、繁殖和分布方面的重要作用。这些发现为减轻 ARGs 的传播和相关的公共卫生风险提供了更深入的见解。

       To better understand the potential genic communication and dissemination of antibiotic resistance genes (ARGs) in different environmental matrices, the differences of ARG profiles between river surface water and sediments were explored. Metagenomic analysis was applied to investigate the comprehensive ARG profiles in water and sediment samples collected from the highly human-impacted catchment of the Beijiang River and its river source. A total of 135 ARG subtypes belonging to 18 ARG types were identified. Generally, ARGs in surface water were more diverse and abundant than those in sediments. ARG profiles in the surface water and sediment samples were distinct from each other, but some ARGs were shared by the surface water and sediments. Results revealed that multidrug and bacitracin resistance genes were the predominant ARGs types in both surface water (0.30, 0.17 copies/cell) and sediments (0.19, 0.15 copies/cell). 73 ARG subtypes were shared by the water and sediment samples and had taken over 90% of the total detected ARG abundance. Most of the shared ARGs are resistant to the clinically relevant antibiotics. Furthermore, significant correlations between the ARGs and 21 shared genera or mobile genetic elements (MGEs) (plasmids and integrons) were found in surface water and sediments, suggesting the important role of genera or MGEs in shaping ARGs profiles, propagation and distribution. These findings provide deeper insight into mitigating the propagation of ARGs and the associated risks to public health.

https://www.sciencedirect.com/science/article/abs/pii/S0147651318304275