Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , Xiamen, 361021, People's Republic of China.
Environ Sci Technol. 2014 Jul 15;48(14):8188-95. doi: 10.1021/es501646n. Epub 2014 Jun 26.
Bacterial antibiotic resistance (BAR) in drinking water has become a global issue because of its risks on the public health. Usually, the antibiotic concentrations in drinking water are too low to select antibiotic resistant strains effectively, suggesting that factors other than antibiotics would contribute to the emergence of BAR. In the current study, the impacts of mutagenic disinfection byproducts (DBPs) on BAR were explored, using four typical DBPs: dibromoacetic acid, dichloroacetonitrile, potassium bromate, and 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX). After exposure to DBPs, resistances to 10 individual antibiotics and multiple antibiotics were both raised by various levels, norfloxacin and polymycin B resistances were enhanced even greater than 10-fold compared with control. MX increased the resistance most observably in the selected DBPs, which was consistent with its mutagenic activity. The resistant mutants showed hereditary stability during 5-day culturing. The increase of BAR was caused by the mutagenic activities of DBPs, since mutation frequency declined by adding ROS scavenger. Mutagenesis was further confirmed by sequencing of the related genes. Our study indicated that mutagenic activities of the selected DBPs could induce antibiotic resistance, even multidrug resistance, which may partially explain the lack of agreement between BAR and antibiotic levels in drinking water.
饮用水中的细菌抗生素耐药性（BAR）已成为一个全球性问题，因为它对公众健康存在风险。通常，饮用水中的抗生素浓度太低，无法有效选择抗生素耐药菌株，这表明除抗生素以外的其他因素也会促成 BAR 的出现。在本研究中，使用四种典型的消毒副产物（DBPs）：二溴乙酸、二氯乙腈、溴酸钾和 3-氯-4-（二氯甲基）-5-羟基-2（5H）-呋喃酮（MX），探讨了致突变性 DBPs 对 BAR 的影响。在接触 DBPs 后，对 10 种单独抗生素和多种抗生素的耐药性均有不同程度的提高，与对照相比，诺氟沙星和多粘菌素 B 的耐药性提高了 10 倍以上。MX 在选定的 DBPs 中最显著地增加了耐药性，这与其致突变活性一致。在 5 天的培养过程中，耐药突变体表现出遗传稳定性。BAR 的增加是由 DBPs 的致突变活性引起的，因为添加 ROS 清除剂会降低突变频率。通过相关基因的测序进一步证实了突变。我们的研究表明，所选 DBPs 的致突变活性可诱导抗生素耐药性，甚至多药耐药性，这可能部分解释了饮用水中 BAR 与抗生素水平之间缺乏一致性的原因。
