摘要

       为了更好地了解噬菌体在水生环境中抗生素抗性基因 (ARG) 传播中的作用，从中国四川阜南河采集了 36 份水样。通过 PCR 评估了噬菌体颗粒 DNA 中 15 个临床相关 ARG 和一个 1 类整合子基因 int1 的出现。通过定量 PCR (qPCR) 确定 ARG（blaCTX-M、sul1 和 aac-(6')-1b-cr）的丰度。在测试样本的噬菌体颗粒 DNA 中发现 int1 基因的高流行率（66.7%），其次是 sul1（41.7%）、sul2（33.3%）、blaCTX-M（33.3%）、aac-（6'） -lb-cr (25%)、aph(3')-IIIa (16.7%) 和 ermF (8.3%)。 qPCR 数据显示，在医院（站点 7）和废水处理厂 (WWTP)（站点 10）附近收集的样本中基因拷贝 (GC) 数量较高（P <.05）。特别是 aac-(6')-lb-cr 基因的绝对丰度显着高于 blaCTX-M 和 sul1 基因，位点 7 的基因拷贝 (GC) 数为 5.73log10copy/mL 和 4.99log10copy/mL对于位点 10。据我们所知，这是第一项报告在来自水生环境的噬菌体 DNA 中存在 sul2、aac-(6')-lb-cr、ermF 和 aph(3')-IIIa 基因的研究。我们的研究结果强调了 ARGs 在水生环境中通过噬菌体传播的潜力。

       To better understand the role that bacteriophages play in antibiotic resistance genes (ARGs) dissemination in the aquatic environment, 36 water samples were collected from the Funan River in Sichuan, China. The occurrence of 15 clinically relevant ARGs and one class 1 integron gene int1 in phage-particle DNA were evaluated by PCR. The abundance of ARGs (blaCTX-M, sul1, and aac-(6′)-1b-cr) was determined by quantitative PCR (qPCR). High prevalence of the int1 gene (66.7%) was found in the phage-particle DNA of tested samples, followed by sul1 (41.7%), sul2 (33.3%), blaCTX-M (33.3%), aac-(6′)-lb-cr (25%), aph(3′)-IIIa (16.7%), and ermF (8.3%). The qPCR data showed higher gene copy (GC) numbers in samples collected near a hospital (site 7) and a wastewater treatment plant (WWTP) (site 10) (P < .05). Particularly the absolute abundance of aac-(6′)-lb-cr gene was significantly higher than the blaCTX-M and sul1 genes with the gene copy (GC) numbers of 5.73 log10 copy/mL for site 7 and 4.99 log10 copy/mL for site 10. To our best knowledge, this is the first study to report the presence of sul2, aac-(6′)-lb-cr, ermF and aph(3′)-IIIa genes in bacteriophage DNA derived from aquatic environments. Our findings highlight the potential of ARGs to be transmitted via bacteriophages in the aquatic environment.

https://www.sciencedirect.com/science/article/abs/pii/S0048969718301736