摘要
       噬菌体是普遍分布的比细菌更丰富的原核病毒。作为其生命周期的结果，噬菌体可以绑定其宿主的部分遗传物质，包括抗生素抗性基因（ARG），其在称为转导的过程中释放噬菌体颗粒转移。 ARGs在致病菌中的传播目前构成严重的全球健康问题。在本研究中，通过qPCR筛选出10种ARG（blaTEM，blaCTX-M-1组，blaCTX-M-9组，blaOXA-48，blaVIM，mecA，sul1）的新鲜蔬菜（莴苣，菠菜和黄瓜） ，qnrA，qnrS和armA）在他们的病毒DNA部分。在大肠杆菌宿主菌株的繁殖实验之前和之后分析噬菌体DNA中ARG的存在以评估噬菌体颗粒感染宿主的能力。在所有基质的噬菌体DNA部分中发现ARG，尽管具有不同的值。莴苣和土壤中的ARG流行率显着较高，最常见的是β-内酰胺酶。在繁殖实验之后，在所有四种基质的样品中观察到噬菌体颗粒中ARG密度的增加，证实部分分离的噬菌体颗粒具有感染性。这项研究揭示了蔬菜基质和农田土壤中含有大量游离的复制型ARG噬菌体颗粒。这些颗粒被建议作为在这些环境中抵抗转移的载体，在这些环境中它们可以持续很长时间，并可能产生新的耐药菌株。摄入这些移动遗传因素也可能有利于出现新的抵抗力，这是以前未曾考虑的风险。

       Bacteriophages are ubiquitously distributed prokaryotic viruses that are more abundant than bacteria. As a consequence of their life cycle, phages can kidnap part of their host's genetic material, including antibiotic resistance genes (ARGs), which released phage particles transfer in a process called transduction. The spread of ARGs among pathogenic bacteria currently constitutes a serious global health problem. In this study, fresh vegetables (lettuce, spinach and cucumber), and cropland soil were screened by qPCR for ten ARGs (blaTEM, blaCTX-M-1 group, blaCTX-M-9 group, blaOXA-48, blaVIM, mecA, sul1, qnrA, qnrS and armA) in their viral DNA fraction. The presence of ARGs in the phage DNA was analyzed before and after propagation experiments in an Escherichia coli host strain to evaluate the ability of the phage particles to infect a host. ARGs were found in the phage DNA fraction of all matrices, although with heterogeneous values. ARG prevalence was significantly higher in lettuce and soil, and the most common overall were β-lactamases. After propagation experiments, an increase in ARG densities in phage particles was observed in samples of all four matrices, confirming that part of the isolated phage particles were infectious. This study reveals the abundance of free, replicative ARG-containing phage particles in vegetable matrices and cropland soil. The particles are proposed as vehicles for resistance transfer in these environments, where they can persist for a long time, with the possibility of generating new resistant bacterial strains. Ingestion of these mobile genetic elements may also favor the emergence of new resistances, a risk not previously considered.

https://www.ncbi.nlm.nih.gov/pubmed/29567433