College of Environmental Science and Engineering, China West Normal University, Nanchong 637009, China.
College of Life Sciences, China West Normal University, Nanchong 637002, China.
Sci Total Environ. 2022 Jul 15;830:154739. doi: 10.1016/j.scitotenv.2022.154739. Epub 2022 Mar 22.
Rivers in agricultural regions serve as an important sink for livestock and poultry farm runoff, fertilizer runoff, and country living sewage, which could bring antibiotic resistance genes (ARGs) contaminations. However, the diversity and distribution of ARGs has not been well documented in the agricultural influenced river. Here, the diversity of ARGs, and their relationship with biochemical factors were determined in the surface water in an agricultural region of the Jialing River and its five rural branches. The 218 unique ARGs encoding resistance to eight major antibiotic classes have been detected using high-throughput quantitative PCR. The branches of the river had a remarkably higher abundance of ARGs than the mainstream. The aminoglycoside, beta_Lactamase, MLSB, and Multidrug resistance genes were significantly enriched in the branches compared to the mainstream. Compared with the mainstream, the ARGs profiles in the branches showed obvious higher spatial variability. Significant correlation between ARGs profiles and bacterial community structures were observed, and network analysis further showed that the ARGs were associated with their potential hosts, such as Ottowia and Novosphingobium. Redundancy discrimination analysis revealed that Cu content has a significant contribution to the increase of ARGs in the river. The microbial diversity index was negatively correlated with the abundance of the ARGs. These results provide evidence for the enrichment of ARGs in the agricultural influenced river and branches due to the joint influence of chemical and microbial variables.
在农业地区，河流是牲畜和家禽养殖场径流、肥料径流和农村生活污水的重要汇，这些可能会带来抗生素耐药基因（ARGs）的污染。然而，受农业影响的河流中 ARGs 的多样性和分布情况尚未得到充分记录。在这里，我们采用高通量定量 PCR 技术，确定了嘉陵江农业区及其五条农村支流的地表水中 ARGs 的多样性及其与生化因子的关系。检测到了 218 种独特的 ARGs，这些基因能够编码对抗八种主要抗生素类别的耐药性。与主流相比，支流的 ARGs 丰度明显更高。与主流相比，支流水体中的氨基糖苷类、β-内酰胺酶、MLSB 和多药耐药基因明显更为丰富。与主流相比，支流水体中的 ARGs 图谱表现出明显更高的空间变异性。ARGs 图谱与细菌群落结构之间存在显著的相关性，网络分析进一步表明，ARGs 与潜在宿主（如 Ottowia 和 Novosphingobium）有关。冗余判别分析显示，Cu 含量的增加对河流中 ARGs 的增加有显著贡献。微生物多样性指数与 ARGs 的丰度呈负相关。这些结果为农业影响河流及其支流中 ARGs 的富集提供了证据，这是由于化学和微生物变量的共同影响。
