摘要

    抗菌素耐药基因（ARG）对环境和人类健康构成了严重威胁。但是，很少有研究解决与养殖鱼类及其水产养殖环境有关的ARG的丰富和分布。在这里，我们通过定量PCR技术对斑点鲈鱼（Lateolabrax maculatus）以及周围环境（水和沉积物）中的细菌群落进行了定量分析，分析了肠道和gARG的丰度和分布。为此，我们在广东省珠海市（中国最大的斑点鲈鱼养殖场）采样了六个水产养殖池塘。肠道中主要的ARG是floR，sul2和tetM-01，腮中是tetQ，sul1和floR。在环境中，sul1，sul2和cmlA1-01的拷贝数明显更高。此外，发现肠道，g和环境中的微生物群之间存在显着差异。与其他来源相比，前者与环境微生物群落更为相似。鱼肠和g微生物群分别主要是梭菌和放线菌。相反，变形杆菌在水和沉积物中占主导地位。相关分析表明，梭菌和放线菌分别与floR和tetQ正相关，表明这些微生物是ARGs的潜在宿主。我们的结果表明，养殖鱼类中的ARGs与水产养殖环境存在显着差异，从而为鉴定水生鱼类中的有害ARGs提供了有价值的参考。

    Antimicrobial resistance genes (ARGs) pose a serious threat to environment and human health. However, few studies address the abundance and distribution of ARGs associated with farmed fish and their aquaculture environment. Here we conducted an analysis of the abundance and distribution of gut and gill ARGs by quantitative PCR techniques associated with the spotted sea bass (Lateolabrax maculatus) as well as the bacterial communities in the surrounding environment (water and sediment). For this purpose, we sampled six aquaculture ponds in Zhuhai, Guangdong Province, the largest spotted sea bass cultivation site in China. Predominant ARGs were floR, sul2, and tetM-01 in the gut and tetQ, sul1, and floR in the gills. The copy numbers of sul1, sul2, and cmlA1-01 were significantly higher in the environment. Moreover, significant differences were found among the microbiota of the gut, gills, and environment. The former was more similar to those of the environmental microbial communities compared with other sources. The fish gut and gill microbiota were predominantly populated by Fusobacteria and Actinobacteria, respectively. In contrast, Proteobacteria were dominant in water and sediment. Correlation analysis showed that Fusobacteria and Actinobacteria positively correlated with floR and tetQ, respectively, indicating that these microbes were potential hosts for ARGs. Our results showed that ARGs in farmed fish showed marked difference with their aquaculture environment, thus providing a valuable reference for identifying deleterious ARGs in aquatic fish.

    https://www.sciencedirect.com/science/article/abs/pii/S0269749121002943