摘要

超抗生素抗性基因（SARG）表现出比其他抗生素抗性基因更严重的威胁，但在环境中没有得到足够的重视。该研究探讨了长江下游和附近污水处理厂（WWTP）和饮用水处理厂（DWTP）两种典型SARG，MCR-1和NDM-1及其宿主细菌的流行和抗生素耐受性特征。 ）。结果表明，MCR-1和NDM-1在污水处理厂的进水和生物单元中普遍存在。它们的寄主细菌被有效去除，但2.49×108copies / L MCR-1和7.00×106copies / L NDM-1仍然在流出物中持久存在。在长江中，检测到MCR-1和NDM-1具有比污水处理厂出水更高的丰度和抗生素耐受性，并且受到附近水污染和人类活动的显着影响。在DWTP中，检测到MCR-1和NDM-1，进水中的平均值为5.56×107copies / L和2.14×105copies / L.它们的宿主细菌在出水中检测不到，但两种SARG仍然持续存在，分别为1.39×107copies / L和6.29×104copies / L，并且在污泥中大量富集。分子生态学网络证明了DWTP中MCR-1 / NDM-1与细菌群落之间存在广泛的宿主关系。冗余分析发现MCR-1与COD和NH3-N呈正相关，而与浊度呈负相关。此外，宿主细菌MCR-1与NO3 - N呈正相关，与COD和NH3-N呈负相关。 NDM-1与浊度呈正相关，NDM-1寄主细菌与COD和NO2 - N呈正相关。该研究表明，污水处理厂无法有效清除大量排放到长江中的SARG。然后将它们运送到DWTP中，污水中持久的SARG可能会转移到人体内，从而对公共健康构成巨大威胁。

The super antibiotic resistance genes (SARGs) demonstrate more severe threats than other antibiotic resistance genes while have not received enough attention in the environment. The study explored the prevalence and the antibiotic tolerance profiles of two typical SARGs, MCR-1 and NDM-1, and their hosting bacteria in the downstream of the Yangtze River and the nearby wastewater treatment plant (WWTP) and drinking water treatment plant (DWTP). Results indicated that MCR-1 and NDM-1 were prevalent in the influent and biological units of the WWTP. Their hosting bacteria were effectively removed, but 2.49 × 108 copies/L MCR-1 and 7.00 × 106 copies/L NDM-1 were still persistent in the effluent. In the Yangtze River, MCR-1 and NDM-1 were detected with higher abundance and antibiotic tolerance than the WWTP effluent and were significantly affected by nearby water contamination and human activities. In the DWTP, MCR-1 and NDM-1 were detected with average values 5.56 × 107 copies/L and 2.14 × 105 copies/L in the influent. Their hosting bacteria were undetectable in the effluent, but the two SARGs were still persistent with 1.39 × 107 copies/L and 6.29 × 104 copies/L, and were greatly enriched in the sludge. Molecular ecological networks demonstrated wide hosting relationships between MCR-1/NDM-1 and bacteria community in the DWTP. Redundancy analysis found that MCR-1 positively correlated with COD and NH3-N, while negatively correlated with turbidity. Additionally, MCR-1 hosting bacteria positively correlated with NO3--N and negatively correlated with COD and NH3-N. NDM-1 positively correlated with turbidity and NDM-1 hosting bacteria positively correlated with COD and NO2--N. The study demonstrated that the WWTP could not effectively remove SARGs with high amount of them being discharged into the Yangtze River. Then they were transported into the DWTP and the persistent SARGs in the effluent would probably be transferred into human, thus imposing great threats on public health.

https://www.ncbi.nlm.nih.gov/pubmed/30321718