摘要

废水处理厂（WWTP）从各种来源收集废水，以进行多步处理过程。通过混合多种细菌并促进其接近，污水处理厂构成了产生抗生素抗性细菌的潜在热点。人们已经对污水处理厂将抗生素抗性基因（ARGs）从环境水库传播到人类病原体的潜力表示了担忧。我们利用epicPCR（乳液，配对分离和串联PCR）来检测两个污水处理厂中ARG的细菌宿主。我们确定了进水和出水中四个抗性相关基因（tetM，int1，qacEΔ1和blaOXA-58）的宿主分布。这些抗性基因的细菌宿主在污水处理厂进水和污水之间变化，污水中的宿主范围通常减小。通过16S rRNA基因测序，确定携带抗性基因的细菌包括丰富和稀有的分类单元。我们的结果表明，研究的污水处理厂在治疗过程中主要成功地降低了抗性基因的宿主范围。不过，在某些情况下，污水中细菌群中仍含有抗性基因，而细菌中没有携带这些基因。通过在WWTP细菌群落中对耐药性相关基因宿主进行详尽的概况分析，epicPCR的应用为我们的耐药性基因风险估计提供了更高的精确度。

Wastewater treatment plants (WWTPs) collect wastewater from various sources for a multi-step treatment process. By mixing a large variety of bacteria and promoting their proximity, WWTPs constitute potential hotspots for the emergence of antibiotic resistant bacteria. Concerns have been expressed regarding the potential of WWTPs to spread antibiotic resistance genes (ARGs) from environmental reservoirs to human pathogens. We utilized epicPCR (Emulsion, Paired Isolation and Concatenation PCR) to detect the bacterial hosts of ARGs in two WWTPs. We identified the host distribution of four resistance-associated genes (tetM, int1, qacEΔ1and blaOXA-58) in influent and effluent. The bacterial hosts of these resistance genes varied between the WWTP influent and effluent, with a generally decreasing host range in the effluent. Through 16S rRNA gene sequencing, it was determined that the resistance gene carrying bacteria include both abundant and rare taxa. Our results suggest that the studied WWTPs mostly succeed in decreasing the host range of the resistance genes during the treatment process. Still, there were instances where effluent contained resistance genes in bacterial groups not carrying these genes in the influent. By permitting exhaustive profiling of resistance-associated gene hosts in WWTP bacterial communities, the application of epicPCR provides a new level of precision to our resistance gene risk estimates.

https://academic.oup.com/femsec/article/94/4/fiy038/4919723