摘要
      抗微生物耐药性（AMR）是一场威胁人类、动物和环境健康的全球性危机。自然环境，特别是水资源，已被公认为AMR的蓄水池和传播途径；然而，城市岩溶含水层系统一直被忽视。这是一个令人担忧的问题，因为这些含水层系统为全球约10%的人口提供饮用水；然而，城市对这些脆弱含水层抵抗力的影响却很少被探讨。本研究使用高通量qPCR来确定肯塔基州鲍灵格林市发展中的城市岩溶地下水系统中抗微生物基因（ARG）的发生率和相对丰度。每周对全市10个地点进行采样，分析85个ARG，以及7个人类和动物来源的微生物源追踪（MST）基因，提供了对城市岩溶地下水阻力的时空理解。为了进一步了解这种环境中的ARGs，考虑了与抗性相对丰度有关的潜在驱动因素（土地利用、喀斯特特征类型、季节、粪便污染源）。MST标记突出了人类对这种喀斯特环境中的抗性的显著影响。靶向基因的浓度在样本周之间有所不同，但无论岩溶特征类型或季节如何，所有靶向ARG都在整个含水层中普遍存在，磺酰胺（sul1）、季铵化合物（qacE）和氨基糖苷（strB）类抗菌药物的浓度都很高。在夏季和秋季以及春季，发现了更高的患病率和相对丰度。线性判别分析表明，与季节相比，岩溶特征类型对含水层ARGs的影响更大，粪便污染源的影响最小。这些发现有助于制定有效的AMR管理和缓解策略。
Abstract
Antimicrobial resistance (AMR) is a global crisis threatening human, animal, and environmental health. The natural environment, specifically water resources, has been recognized as a reservoir and dissemination pathway for AMR; however, urban karst aquifer systems have been overlooked. This is a concern as these aquifer systems provide drinking water to about 10 % of the global population; yet, the urban influence on the resistome in these vulnerable aquifers is sparingly explored. This study used high-throughput qPCR to determine the occurrence and relative abundance of antimicrobial resistant genes (ARG) in a developing urban karst groundwater system in Bowling Green, KY. Ten sites throughout the city were sampled weekly and analyzed for 85 ARGs, as well as seven microbial source tracking (MST) genes for human and animal sources, providing a spatiotemporal understanding of the resistome in urban karst groundwater. To further understand ARGs in this environment, potential drivers (landuse, karst feature type, season, source of fecal pollution) were considered in relation to the resistome relative abundance. The MST markers highlighted a prominent human influence to the resistome in this karst setting. The concentration of targeted genes varied between the sample weeks, but all targeted ARGs were prevalent throughout the aquifer regardless of karst feature type or season, with high concentrations captured for sulfonamide (sul1), quaternary ammonium compound (qacE), and aminoglycoside (strB) antimicrobial classes. Higher prevalence and relative abundance were detected during the summer and fall seasons, as well as at the spring features. Linear discriminant analysis suggested that karst feature type had higher influence on ARGs in the aquifer compared to season and the source of fecal pollution had the least influence. These findings can contribute to the development of effective management and mitigation strategies for AMR.

https://www.sciencedirect.com/science/article/abs/pii/S0048969723011877