水产品及其环境中致病性副溶血弧菌(VP)产生的耐热溶血素（TDH）和生物被膜(BF)是引起食物中毒的重要危害因子，腐败希瓦氏菌(SP)与VP共存可对其危害因子生成产生影响，为食品安全评估和控制带来新的挑战。但目前缺乏SP对VP TDH/BF形成作用效应及机制的研究。基于群体感应理论，本研究首先采用基因敲除技术构建VP群体感应信号系统缺失系列突变株，然后将SP分别与VP、VP系列突变株共培养，以荧光定量PCR检测tdh基因表达，荧光原位杂交和共聚焦显微技术观察BF微观形貌及组成特征，明确共存体系下SP对VP TDH/BF形成的作用效应；通过对比基因敲除前后作用效应的改变，探明SP对VP的作用途径；采用信号分子报告菌和LC-MS-MS法对与作用途径相关的关键信号分子进行测定，并明确其与作用效应的动态级联规律，探明SP对VP的作用规律。本项目将为SP共存条件下VP危害因子评估及控制提供理论依据。

Thermostable hemolysin (TDH) and biofilm produced by pathogenic VP (Vibrio parahaemolyticus) in aquatic products and environment are considered to be the most important hazard factors of food poison and food contamination. SP (Shewanella putrefaciens), coexisting with VP, can affect the generation of hazard factors, and bring new challenges for food security assessment and control. At present, the studies focusing on the effects of actions and mechanism of SP on VP THD/biofilm formation are scarce. Based on the theory of quorum sensing, this study will build a series of quorum sensing signal system deletion mutant of VP with gene knockout technology, co-culture SP with VP and VP mutants respectively, ascertain the effects of actions of SP on the TDH production and biofilm formation of VP in coexisting system by detecting the expression differences of gene TDH with FQ-PCR (fluorescence quantitative polymerase chain reaction) and detecting the micromorphology and composition characteristics of biofilm with FISH (fluorescence in situ hybridization) and LSCM (laser scanning confocal microscopy). By contrasting the effects of actions of SP on VP before and after gene knock-out the function pathway of SP to VP is ascertained. The key signal molecules related to the function pathway is detected by signal molecular reporter bacteria detection and LC-MS-MS. The regular pattern of dynamic cascade of signal molecules and the effects of actions are clarified, and the action law of SP to VP can be well researched. This study will provide theoretical basis for the food safety hazard assessment and the control in co-existing condition of VP and SP.