摘要

       众所周知，雨水径流会导致城市河流中细菌含量的增加。然而，人们对其对城市流域抗生素抗性基因 (ARG) 的影响知之甚少。本研究旨在表征城市流域各种环境区室的 ARG 组成，并量化微生物和 ARG 在潮湿天气条件下对城市河流的贡献。 Shotgun宏基因组结果表明，潮湿天气流中的ARG丰度显着高于基流。多药耐药基因是环境样本中最常见的 ARG 类型。路堤土壤和街道清扫样品中含有丰富的万古霉素抗性基因。使用 SourceTracker 进行的分析估计，雨水排放口水是潮湿天气流动期间城市河流中微生物 (54-57%) 和 ARGs (82-88%) 的最大贡献者。此外，街道清扫的结果表明，街道冲刷是雨水排放排放水中微生物 (41-45%) 和 ARGs (92-96%) 的最大已知来源。 Pantoea 和 Pseudomonas 与最高数量的 ARG 相关，并且在与雨水相关的样本中最为丰富。这项研究的结果可以提高我们对城市河流中 ARG 的了解，这是将环境 ARG 与公众联系起来的重要媒介。

       Stormwater runoff has been known to cause increases in bacterial loadings in urban streams. However, little is known about its impacts on antibiotic resistance genes (ARGs) in urban watersheds. This study was performed to characterize the ARG composition of various environmental compartments of an urban watershed and to quantify their contributions of microbes and ARGs to an urban stream under wet weather conditions. Shotgun metagenomic results showed that the ARG abundance in wet weather flow was significantly higher than in base flow. Multidrug resistance genes were the most common ARG type across environmental samples. Vancomycin resistance genes were abundant in embankment soil and street sweeping samples. Analyses using SourceTracker estimated storm drain outfall water to be the biggest contributor of microbes (54–57%) and ARGs (82–88%) in the urban stream during wet weather flows. Furthermore, results on street sweepings showed that wash-off from streets was the biggest known contributor of microbes (41–45%) and ARGs (92–96%) in storm drain outfall water. Pantoea and Pseudomonas were associated with the highest numbers of ARGs and were most abundant in stormwater-related samples. Results from this study can advance our knowledge about ARGs in urban streams, an important medium linking environmental ARGs to the general public.

https://pubs.acs.org/doi/abs/10.1021/acs.est.8b01219