College of Life Sciences, Henan Normal University, Xinxiang 453007, China; Key Laboratory for Microorganisms and Functional Molecules (Henan Normal University), University of Henan Province, Xinxiang 453007, China.
College of Life Sciences, Henan Normal University, Xinxiang 453007, China.
Sci Total Environ. 2018 Oct 15;639:617-623. doi: 10.1016/j.scitotenv.2018.05.213. Epub 2018 May 26.
Horizontal transfer of ARGs was generally considered to be mediated by three methods - transformation, conjugation and transduction through phages - during which the contribution of bacteriophages to gene transfer in the environment is unclear or even questioned. In this study, a multiple-antibiotic-resistant Escherichia coli strain and its phage (YZ1) were isolated from a municipal wastewater treatment system. The results of the morphological and genomic analyses of phage YZ1 showed that it is a member of the T7 viral genus in the subfamily Autographivirinae. Its genome is similar to that of the E. coli phage K1F in both organization and sequence and does not encode ARGs. However, 28 paired reads in the raw sequencing data aligned to ARGs, including those promoting β-lactam, aminoglycoside, and fluoroquinolone resistance, among others. Quantitative PCR showed that ARGs were present in bacteriophage DNA (approximately 10 copies/mL) and were also detected in the bacterial host DNA. The results suggested that while infrequent, some ARG-carrying transducing phages were presumably generated by erroneous packaging during infection of antibiotic-resistant bacteria, which may create the possibility of horizontal transfer of ARGs.
水平基因转移通常被认为是由三种方法介导的 - 转化、共轭和噬菌体转导 - 在这三种方法中，噬菌体在环境基因转移中的贡献尚不清楚，甚至受到质疑。在本研究中，从城市污水处理系统中分离到一株多抗生素抗性大肠杆菌及其噬菌体（YZ1）。噬菌体 YZ1 的形态学和基因组分析结果表明，它是 T7 病毒属在 Autographivirinae 亚科中的一个成员。其基因组在组织和序列上与大肠杆菌噬菌体 K1F 相似，不编码 ARGs。然而，原始测序数据中的 28 对reads 与 ARGs 对齐，包括促进β-内酰胺、氨基糖苷和氟喹诺酮类药物耐药性的基因等。定量 PCR 显示，噬菌体 DNA 中存在 ARGs（约 10 拷贝/mL），并且在细菌宿主 DNA 中也检测到了 ARGs。结果表明，尽管频率较低，但一些携带 ARG 的转导噬菌体可能是在感染抗生素抗性细菌时发生错误包装产生的，这可能为 ARGs 的水平转移创造了可能性。
