Abstract：
Aquatic ecosystems are crucial in the antimicrobial resistance cycle. While intracellular DNA has been extensively studied to understand human activity\'s impact on antimicrobial resistance gene (ARG) dissemination, extracellular DNA is frequently overlooked. This study examines the effect of anthropogenic water pollution on microbial community diversity, the resistome, and ARG dissemination. We analyzed intracellular and extracellular DNA from wastewater treatment plant effluents and lake surface water by shotgun sequencing. We also conducted experiments to evaluate anthropogenic pollution\'s effect on transforming extracellular DNA (using Gfp-plasmids carrying ARGs) within a natural microbial community. Chemical analysis showed treated wastewater had higher anthropogenic pollution-related parameters than lake water. The richness of microbial community, antimicrobial resistome, and high-risk ARGs was greater in treated wastewaters than in lake waters both for intracellular and extracellular DNA. Except for the high-risk ARGs, richness was significantly higher in intracellular than in extracellular DNA. Several ARGs were associated with mobile genetic elements and located on plasmids. Furthermore, Gfp-plasmid transformation within a natural microbial community was enhanced by anthropogenic pollution levels. Our findings underscore anthropogenic pollution\'s pivotal role in shaping microbial communities and their antimicrobial resistome. Additionally, it may facilitate ARG dissemination through extracellular DNA plasmid uptake.
摘要：
水生生态系统在抗微生物剂耐药周期中至关重要。虽然细胞内DNA已被广泛研究，以了解人类活动对抗菌药物抗性基因（ARG）传播的影响，细胞外DNA经常被忽视。本研究考察了人为水污染对微生物群落多样性的影响，耐药性，ARG传播。我们通过shot弹枪测序分析了废水处理厂废水和湖泊地表水中的细胞内和细胞外DNA。我们还进行了实验，以评估人为污染对天然微生物群落中转化细胞外DNA（使用携带ARG的Gfp质粒）的影响。化学分析表明，处理后的废水比湖水具有更高的人为污染相关参数。丰富的微生物群落，抗菌素耐药性，对于细胞内和细胞外DNA，处理过的废水中的高风险ARG都比湖水中的高。除了高风险的ARGs,细胞内DNA的丰富度明显高于细胞外DNA。几个ARG与可移动的遗传元件相关，并位于质粒上。此外，人为污染水平增强了天然微生物群落中的Gfp质粒转化。我们的发现强调了人为污染在塑造微生物群落及其抗微生物耐药性方面的关键作用。此外,它可能通过细胞外DNA质粒摄取促进ARG传播。
