摘要

       基于高通量测序的宏基因组方法被用于综合研究紫外线对微生物群落结构的影响，以及生物处理废水中抗生素抗性基因 (ARG) 和移动遗传元件 (MGE) 的多样性和丰度。紫外线照射后，废水中的气单胞菌和盐单胞菌等优势属几乎消失，而假单胞菌和芽孢杆菌等一些次要属的相对丰度增加了数十倍。宏基因组分析表明，样品中可检测到 14 种类型的 159 个 ARG，500 mJ/cm2 的辐射使它们的总相对丰度从 31.68 ppm 明显增加到 190.78 ppm，这得到了定量实时 PCR 的支持。假单胞菌携带的多药耐药基因和芽孢杆菌携带的杆菌肽抗性基因bacA作为显性持久性ARGs，主要促成了ARGs丰度的增加。辐射诱导的细菌群落转移和 MGEs 复制可能会驱动抵抗组的改变。这些发现可能会为紫外线辐射对废水中抗生素耐药性的影响背后的机制提供新的线索。

       High-throughput sequencing-based metagenomic approaches were used to comprehensively investigate ultraviolet effects on the microbial community structure, and diversity and abundance of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in biologically treated wastewater. After ultraviolet radiation, some dominant genera, like Aeromonas and Halomonas, in the wastewater almost disappeared, while the relative abundance of some minor genera including Pseudomonas and Bacillus increased dozens of times. Metagenomic analysis showed that 159 ARGs within 14 types were detectable in the samples, and the radiation at 500 mJ/cm2 obviously increased their total relative abundance from 31.68 ppm to 190.78 ppm, which was supported by quantitative real time PCR. As the dominant persistent ARGs, multidrug resistance genes carried by Pseudomonas and bacitracin resistance gene bacA carried by Bacillus mainly contributed to the ARGs abundance increase. Bacterial community shift and MGEs replication induced by the radiation might drive the resistome alteration. The findings may shed new light on the mechanism behind the ultraviolet radiation effects on antibiotic resistance in wastewater.

https://www.sciencedirect.com/science/article/abs/pii/S0043135416304249