环境中的病原菌对农产品安全、人类健康以及农业经济发展造成极大的威胁。目前环境中病原菌的研究多集中在土壤和单纯的水环境，而病原菌在水体沉积物中的环境行为尚不清楚。大肠杆菌O157:H7作为常见病原菌，具有感染剂量极低、致病性高以及传播范围广等特点。本项目拟以O157:H7为例，以河口沉积物为研究对象，解析沉积物中O157:H7的存活时间及关键调控因子，探讨O157:H7与微生物群落间的相互作用关系，深入剖析主导沉积物再悬浮过程中O157:H7释放的关键因子及相关机制。通过本项目研究，揭示O157:H7在河口沉积物中的环境行为及相应调控机制，为理解外源病原菌与微生物群落相互作用提供新的认识，提升病原菌环境过程的研究水平、发展病原菌污染末端治理和修复技术体系。

The pathogen in the environment can become a reservoir of future infections, which is a threat to food safety, human health and agricultural economy development. Most of the previous studies focused on the soil and water with the role of sediment in pathogen contamination being ignored. Escherichia coli O157:H7, an important pathogen, is dangerous because of its low infective dose and high pathogenicity. In this project, the survival of O157:H7 in estuarine sediments and the interaction between invading O157:H7 and indigenous microbial community will be investigated. The internal mechanism of how the sediment properties affect O157:H7 survival will be revealed. Moreover, the experiment about the release of O157:H7 during sediment suspension will be carried out to provide insight into mechanism of the distribution of O157:H7 in the sediment-water system. The results of this project are expected to provide new knowledge on the survival and transport of O157:H7 in the environment and contribute to the prevention and control of pathogen contamination.