河口水环境微生物被膜中典型金属NPs对ARGs的赋存和转移的影响

河口水体中抗生素抗性基因（ARGs）、金属纳米颗粒物（NPs）和微生物被膜广泛存在，且微生物被膜已被证实是ARGs和金属NPs重要的“汇”。但是，金属NPs对微生物被膜中ARGs的赋存特征、演替规律和转移过程等的影响及机理尚不明确。本项目拟以长江口为研究区域，通过野外调查、现场和实验室模拟及分析相结合，重点利用宏基因组测序、基因编辑和SP-ICP-MS等手段，调查典型金属NPs（ZnO-NPs和Ag-NPs）对河口微生物被膜中ARGs赋存的影响，同时分析金属NPs性质和被膜生物学特性等及其与ARGs赋存之间的关系。此外，分别调查金属NPs对河口细菌和模式细菌形成的单一及混合被膜中ARGs垂直和水平转移的影响，筛选出关键调控基因并构建这些基因缺陷菌株进行验证。最后，结合河口环境因子，阐明金属NPs调控微生物被膜中ARGs赋存和转移的分子机制，为河口水环境安全与健康提供数据支持和科学依据。

Antibiotic resistance genes (ARGs), metal nanoparticles (NPs) and biofilms are widespread in the estuary environment, and biofilms have been proved to be an vital sink of ARGs and metal NPs. However, the influence and mechanism of metallic NPs on the occurrence characteristics, succession rules and transfer process of ARGs in biofilms are still unclear. In this study, based on the field surveys, on-site and laboratory simulation and analysis, the effects of ZnO-NPs and Ag-NPs on the occurrence and abundance of total ARGs, eARGs and iARGs in biofilms in the Yangtze estuary will be investigated by using the method or technique of the metagenomic sequencing, qPCR, gene editing and single particle (SP)-ICP-MS, etc. Furthermore, the analysis of the properties of metal NPs, microbial community and the biological characteristics of biofilms and their relationships with ARGs will be conducted. In addition, the effects of metal NPs on the vertical and horizontal transfer of ARGs in single and mixed biofilms formed by estuarine bacteria or model bacteria will be investigated. In these processes, some key genes will be screened out and these gene-deficient strains will be constructed for verification. Finally, combined with the environmental factors, this study will clarify the molecular mechanism of metal NPs regulating the occurrence and transfer of ARGs in estuarine biofilm. These results will provide new insights for improving the in-depth understanding of the combined pollutions of NPs and ARGs in the estuarine biofilms, which are also beneficial to the governance and evaluation of estuarine water in the future.