Aquatic animals promote antibiotic resistance gene dissemination in water via conjugation: role of different regions within the zebra fish intestinal tract, and impact on fish intestinal microbiota

The aqueous environment is one of many reservoirs of antibiotic resistance genes (ARGs). Fish, as important aquatic animals which possess ideal intestinal niches for bacteria to grow and multiply, may ingest antibiotic resistance bacteria from aqueous environment. The fish gut would be a suitable environment for conjugal gene transfer including those encoding antibiotic resistance. However, little is known in relation to the impact of ingested ARGs or antibiotic resistance bacteria (ARB) on gut microbiota. Here, we applied the cultivation method, qPCR, nuclear molecular genetic marker and 16S rDNA amplicon sequencing technologies to develop a plasmid-mediated ARG transfer model of zebrafish. Furthermore, we aimed to investigate the dissemination of ARGs in microbial communities of zebrafish guts after donors carrying self-transferring plasmids that encode ARGs were introduced in aquaria. On average, 15% of faecal bacteria obtained ARGs through RP4-mediated conjugal transfer. The hindgut...水生环境是抗生素抗性基因（antibiotic resistance genes, ARGs）的众多储存库之一。鱼类作为重要的水生动物，其肠道为细菌的生长繁殖提供了理想的微生态位，可从水生环境中摄入抗生素抗性细菌（antibiotic resistance bacteria, ARB）。鱼类肠道是接合型基因转移的适宜环境，此类转移可携带编码抗生素抗性的基因。然而，目前关于摄入的ARGs或ARB对肠道微生物群的影响仍知之甚少。本研究采用培养法、实时定量聚合酶链式反应（qPCR）、核分子遗传标记以及16S rDNA扩增子测序技术，构建了斑马鱼的质粒介导型ARGs转移模型。此外，本研究旨在探究当向水族箱中引入携带编码ARGs的自主转移质粒的供体菌后，ARGs在斑马鱼肠道微生物群落中的传播扩散情况。平均而言，有15%的粪便细菌通过RP4介导的接合转移获得了ARGs。而后肠……