摘要

抗生素耐药细菌感染是人类健康的主要威胁之一。阐明环境在其传播中的作用的研究仍处于起步阶段，然而，似乎不同的环境可能作为驻留在其微生物群落内的抗生素抗性基因（ARG）的长期储库起作用。越来越多的研究针对暴露于人类活动的水域和土壤中ARGs的存在和持久性;然而，他们很少考虑在这些环境中占主导地位的空间/时间变化。在这里，我们通过比较降雨过程中基因丰度的测量结果与每年的年度降水事件（4mm雨h-1）对ARG（tetA，ermB，blaCTXM，sulII和qnrS）的丰度和分布的影响平均水平在亚高山大河中。然后，ARG丰度在雨季中增加，然后与几个微生物，物理和化学变量相关联，以确定它们的潜在来源。降雨期间ARG丰度的增加（总ARGs：24倍）伴随着总磷，N-NH4和微生物聚集体的增加。我们的研究结果表明中等降雨量对ARGs丰度的强烈影响，并建议将流域作为其来源。然后应该在ARG动力学建模和管理中考虑受人类活动影响的地区适度降雨量的影响。

Infections with antibiotic resistant bacteria are among the major threats for human health. Studies elucidating the role of the environment in their spread are still in their infancy, it, however, seems that different environments might function as a long-term reservoir of antibiotic resistance genes (ARGs) that reside within their microbial communities. An increasing number of studies target the presence and the persistence of ARGs in waters and soils that are exposed to human activities; they, however, rarely consider the spatial/temporal variability that predominate in these environments. Here we evaluated the effect of a moderate rain event (4 mm rain h−1) on the abundance and distribution of ARGs (tetA, ermB, blaCTXM, sulII, and qnrS), by comparing measurements of gene abundances during the rainfall to the yearly average, in the waters of a large subalpine river. ARG abundances, which all increased during the rain event, were then correlated to several microbiological, physical and chemical variables, in order to establish their potential origin. Increments in ARG abundances during rainfall (total ARGs: 24 fold) was concomitant to an increase in total phosphorous, N-NH4, and microbial aggregates. Our results show a strong influence of a moderate rainfall on the abundances of ARGs, and suggest the catchment as their source. The impact of moderate rainfalls in areas exposed to anthropic activities should then be considered in modelling and management of ARG dynamics.

https://www.sciencedirect.com/science/article/pii/S0269749116327427