Abstract：
The migration and dissemination of antibiotics and their corresponding antibiotic resistance genes (ARGs) from pharmaceutical plants through wastewater treatment to the environment introduce exogenous ARGs, increasing the risk of antibiotic resistance. Cephalosporin antibiotics (Ceps) are among the most widely used antibiotics with the largest market scale today, and the issue of resistance is becoming increasingly severe. In this study, a cephalosporin pharmaceutical plant was selected and metagenomic analysis was employed to investigate the dissemination patterns of cephalosporin antibiotics (Ceps) and their ARGs (CepARGs) from the pharmaceutical plant through the wastewater treatment plant to tidal flats sediments. The findings revealed a significant reduction in the total concentration of Ceps by 90.32 % from the pharmaceutical plant\'s Pioneer Bio Reactor (PBR) to the effluent of the wastewater treatment plant, and a notable surge of 172.13 % in the relative abundance of CepARGs. It was observed that CepARGs originating from the PBR could migrate along the dissemination chain, contributing to 60 % of the CepARGs composition in tidal flats sediments. Microorganisms play a crucial role in the migration of CepARGs, with efflux-mediated CepARGs, as an intrinsic resistance mechanism, exhibiting a higher prospensity for migration due to their presence in multiple hosts. While Class I risk CepARGs are present at the pharmaceutical and wastewater plant stages, Class I ina-CepARGs are completely removed during wastewater treatment and do not migrate to the environment. This study reveals the dynamic migration characteristics and potential risk changes regarding Ceps and CepARGs in real dissemination chains, providing new theoretical evidence for the mitigation, control, and risk prevention of CepARGs.
摘要：
抗生素及其相应的抗生素抗性基因（ARGs）通过废水处理向环境的迁移和传播，引入外源ARGs，增加抗生素耐药性的风险。头孢菌素类抗生素（Ceps）是当今使用最广泛，市场规模最大的抗生素之一，抵抗问题日益严峻。在这项研究中,选择了头孢菌素制药厂，并采用宏基因组分析来研究头孢菌素抗生素（Ceps）及其ARG（CepARG）从制药厂通过废水处理厂传播到潮滩沉积物的传播模式。研究结果表明，从制药厂的先锋生物反应器（PBR）到废水处理厂的废水中，Ceps的总浓度显着降低了90.32％，CepARGs的相对丰度显着上升了172.13%。据观察，源自PBR的CepARGs可以沿着传播链迁移，在潮滩沉积物中占CepARGs成分的60％。微生物在CepARGs的迁移中起着至关重要的作用，外排介导的CepARGs，作为一种内在的抵抗机制，由于它们存在于多个宿主中，因此表现出更高的迁移倾向。虽然制药和污水处理厂阶段存在I类风险CepARGs，I类ina-CepARGs在废水处理过程中被完全去除，并且不会迁移到环境中。本研究揭示了Ceps和CepARGs在实际传播链中的动态迁移特征和潜在风险变化，为缓解措施提供新的理论证据，control,和CepARGs的风险预防。
