State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 200092 Shanghai, China.
Environ Sci Technol. 2015 May 5;49(9):5771-8. doi: 10.1021/acs.est.5b00644. Epub 2015 Apr 23.
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).
越来越多的人关注到抗生素耐药基因（ARGs）在废水微生物群落中的传播；然而，作为微生物控制技术的消毒过程，其对抗生素耐药基因转移的影响尚未得到评估。在这项研究中，基于大肠杆菌革兰氏阴性菌株之间的共轭转移模型，探讨了紫外线（UV）消毒和氯化消毒对 ARGs 转移频率的影响。结果表明，UV 消毒和氯化消毒对共轭转移有明显的影响。低剂量的 UV（最高 8 mJ/cm2）对共轭转移的频率几乎没有影响，UV 照射仅减少了细菌数量，但不改变细胞通透性。相比之下，低浓度的氯（最高 40 mg Cl min/L）可显著将共轭转移的频率提高 2-5 倍。生成的氯胺刺激了细菌并提高了细胞通透性。更多的菌毛在共轭细胞表面诱导，这些菌毛充当了 ARGs 转移的途径。高剂量的 UV（>10 mJ/cm2）或氯（>80 mg Cl min/L）大大抑制了 ARG 转移的频率。
