基于宏基因组学探讨东平湖水库的菌群结构、耐药基因谱及其公共健康风险

水库中长时间滞留的水体会成为耐药基因的存储库，因此研究其菌群结构、耐药基因谱及其潜在的健康风险具有重要的公共卫生学意义.本研究以东平湖水库的水体和沉积物为研究对象，采用宏基因组测序技术，系统分析其在旱季和雨季中的菌群结构、耐药基因谱、耐药基因水平转移以及携带耐药基因的致病菌类型.结果表明，与水库沉积物相比，水体中的菌群结构和耐药基因谱受季节影响较大，且旱季的总耐药基因丰度明显高于雨季；水库沉积物中总耐药基因丰度高于水体，但水体中耐药基因的水平转移高于沉积物.本研究共检测到20个耐药基因型，377个耐药基因亚型；杆菌素和万古霉素耐药基因分别是水和沉积物中主要的耐药基因型，变形杆菌和放线菌分别是水体和沉积物中主要携带耐药基因的菌群.此外，本研究还鉴定出30株携带耐药基因的致病菌，包括大肠杆菌、肺炎克雷伯菌、铜绿假单胞菌、肠炎沙门氏菌以及鲍曼不动杆菌，其中有2株大肠杆菌携带毒力因子.综上所述，东平湖水库中的耐药基因不仅种类繁多，而且还存在潜在的公共健康风险；因此定期检测水体环境的菌群结构及其耐药基因谱具有重要的科学价值和现实意义.

Metagenomic Analysis Provides Insights into Bacterial Communities, Antibiotic Resistomes, and Public Health Risks in the Dongping Lake Reservoir

Owing to the long residence times of water, water reservoirs readily contribute to the accumulation of antibiotic resistant gene (ARG). It is of great public health significance to explore bacterial communities, antibiotic resistomes, and the potential public health risks of water reservoirs. In this study, metagenomic sequencing was used to analyze and compare the bacterial communities, ARG profiles, ARG-horizontal transfer, and ARG-carrying pathogens in the water and sediments of the Dongping Lake Reservoir in the dry and the wet seasons. Compared with that of the sediments, the results showed that both the bacterial communities and ARG profiles in the water were significantly influenced by the seasons, and the total ARG abundance in the dry season was significantly higher than that in the wet season. The total ARG abundance in the sediments was higher than that in water, but the horizontal transfer potential of ARG in the water was higher than that in the sediment. A total of 377 ARG subtypes belonging to 20 ARG types were found in this study. Bacitracin and vancomycin resistance genes were the main ARG types in the water and sediments, respectively, and Proteobacteria and Actinobacteria were the major ARG-carrying bacteria in the water and sediments, respectively. In addition, 30 clinical pathogens carrying ARGs were identified, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella enterica, and Acinetobacter bohemicus. More importantly, two Escherichia coli concurrently carried virulence factor and ARG. In summary, this study revealed that a variety of ARG types existed in the Dongping Lake Reservoir, which has posed potential public health risks by contributing to the horizontal transfer of ARG and the accumulation of clinical pathogens. Therefore, it is necessary to regularly monitor the bacterial community and ARG profile in various water bodies.