摘要

       抗生素抗性基因 (ARG) 在废水微生物群落中的传播越来越受到关注；然而，消毒过程作为微生物控制技术，尚未评估其对 ARG 转移的影响。在这项研究中，基于革兰氏阴性大肠杆菌菌株之间的接合转移模型，探索了紫外线 (UV) 消毒和氯化对 ARGs 转移频率的影响。结果表明，紫外线消毒和氯化对共轭转移有明显的影响。低紫外线剂量（高达 8 mJ/cm2）对结合转移的频率几乎没有影响，紫外线照射只会减少细菌数量，但不会改变细胞通透性。相比之下，低氯剂量（高达 40 mg Cl min/L）显着将共轭转移频率提高了 2-5 倍。产生的氯胺刺激细菌并提高细胞通透性。更多的菌毛在接合细胞表面被诱导，作为 ARGs 转移的途径。高剂量的紫外线 (>10 mJ/cm2) 或氯 (>80 mg Cl min/L) 极大地抑制了 ARG 转移的频率。

       Growing attention has been paid to the dissemination of antibiotic resistance genes (ARGs) in wastewater microbial communities; however, the disinfection processes, as microbial control technologies, have not been evaluated for their impacts on ARGs transfer. In this study, the effects of ultraviolet (UV) disinfection and chlorination on the frequency of ARGs transfer have been explored based on the conjugative transfer model between Gram-negative strains of E. coli. The results indicated that UV disinfection and chlorination exhibit distinct influences on the conjugative transfer. Low UV doses (up to 8 mJ/cm2) had little influence on the frequency of conjugative transfer, and UV exposure only decreased the bacterial number but did not change the cell permeability. By comparison, low chlorine doses (up to 40 mg Cl min/L) significantly promoted the frequency of conjugative transfer by 2–5-fold. The generated chloramine stimulated the bacteria and improved the cell permeability. More pilus were induced on the surface of conjugative cells, which acted as pathways for ARGs transfer. The frequency of ARG transfers was greatly suppressed by high doses of UV (>10 mJ/cm2) or chlorine (>80 mg Cl min/L).

https://pubs.acs.org/doi/abs/10.1021/acs.est.5b00644