摘要

      废水特别是工业废水中的各种芳香族化合物在生物反应器中进行生物处理，被认为是抗生素耐药基因（ARGs）的研究热点和贮存库。然而，芳香族化合物降解过程与抗生素耐药性之间的关系却鲜为人知。本文报道了ARGs与芳香族降解基因（ADGs）在生物反应器中的共存现象。我们通过生物反应器实验和10000多个公开的细菌基因组的生物信息学分析证实了这一点。在处理对氨基酚和对硝基酚废水的生物反应器中，我们观察到ARGs的显著富集。携带ARGs和ADGs的潜在宿主主要为假单胞菌、白杆菌、黄杆菌、不动杆菌和伯克霍尔德菌科。基因组分析显示，67.6%的公开获得的含有adg的细菌基因组也含有ARGs。超过80%的伯克霍尔德菌、黄单胞菌、肠杆菌科、不动杆菌、假单胞菌和诺卡氏菌科基因组同时含有ARGs和ADGs，这有力地说明了这些基因的共现性。此外，携带adg的细菌携带的arg数量是仅携带arg的细菌的两倍多。网络分析表明，多药、β-内酰胺、氨基糖苷、大环内酯-林可酰胺-链霉素和多粘菌素耐药基因是与ADGs相关的主要ARGs。综上所述，本文的研究结果提高了对废水生物处理厂中精氨酸（ARG）流行情况的认识，并突出了常规芳香族化合物对精氨酸（ARG）选择和传播影响的潜在风险。

      Various aromatic compounds in wastewater, especially industrial wastewater, are treated by biological processes in bioreactors which are regarded as hotspots and reservoirs of antibiotic resistance genes (ARGs). Yet, little is known about the relationship between the aromatic compound degradation process and antibiotic resistance. Here, we report on the co-occurrence of ARGs and aromatic degradation genes (ADGs) in bacteria in bioreactors. We confirmed this by bioreactor experiments and bioinformatics analysis of over 10,000 publicly available bacterial genomes. We observed a significant enrichment of ARGs in bioreactors treating wastewater that contained p-aminophenol and p-nitrophenol. The potential hosts harboring ARGs and ADGs were mainly Pseudomonas, Leucobacter, Xanthobacter, Acinetobacter, and Burkholderiaceae. Genome analysis revealed that 67.6% of the publicly available bacterial genomes harboring ADGs also harbor ARGs. Over 80% of Burkholderiales, Xanthomonales, Enterobacteriaceae, Acinetobacter, Pseudomonas, and Nocardiaceae genomes harbor both ARGs and ADGs, which strongly suggests the co-occurrence of these genes. Furthermore, bacteria carrying ADGs harbored more than twice the number of ARGs than bacteria only carrying ARGs. Network analysis suggested that multidrug, beta-lactam, aminoglycoside, macrolide-lincosamide-streptogramin, and polymyxin resistance genes are the major ARGs associated with ADGs. Taken together, the presented findings improve the understanding of ARG prevalence in biological wastewater treatment plants, and highlight the potential risk of the effect of regular aromatic compounds on the selection and spread of ARGs.

      https://www.sciencedirect.com/science/article/abs/pii/S0043135419308474?via%3Dihub