海产品中腐败希瓦氏菌冷藏条件下生物膜的粘附效应及其分子机制

腐败希瓦氏菌(Shewanella putrefaciens) 是冷藏条件下海水鱼类的优势腐败菌，具有较强的致腐活性，易粘附于食品及容器表面形成生物被膜，生物被膜的生成增强了微生物的抗逆性，加剧了腐败。生物被膜的生成受到精细的调控，菌体从瞬时的可逆粘附转变为牢固的不可逆粘附是微生物从浮游状态向生物被膜转换的关键。目前针对腐败希瓦氏菌生物被膜的研究主要集中在生物被膜的形成干扰、调控机制，对其在冷藏温度条件下生物被膜形成机制尚未明确。本项目拟采用传统生化培养、理化分析、组学、生物信息学等手段，以腐败希瓦氏菌为研究对象开展生物被膜特征代谢物研究，深入分析异质性，发现其关键调控基因；利用构建突变株，揭示其对被膜生成相关因子、促进因子的调控途径，探明调控通路，阐明腐败希瓦氏菌生物被膜形成机制、粘附效应及其分子机制，进而达到调控生物被膜形成的目的，为生物被膜的应用和防控奠定理论基础。

Shewanella putrefaciens whiccih has a strong spoilage ability is the dominant spoilage bacteriain for marine fish under cold store, it is easy to adhere to the surface of food and container to form biofilm. The biofilm enhances the resistance of microorganisms and the spoilage ability. The formation of biofilm is finely regulated and the transient transition from reversible adhesion to irreversible adhesion is the key factor of the transition from plankton state to biofilm. So far, researches on biofilm of Shewanella putrefaciens mainly focus on the interference of biofilm formation and the regulation mechanism of biofilm in the domestic and foreign food fields, but the mechanism of biofilm formation under the cold storage is not yet clear. In this study, we aim to utilize the traditional biochemical culture, physical and chemical analysis, omics, bioinformatics and other means will be used to study the characteristic metabolites of biofilms with Shewanella putrefaciens, carry out heterogeneity analysis will be carried out deeply and to find its key regulatory genes; . Molecular biology techniques were will be used to construct mutant strains, revealing their regulatory pathways for biofilm-related factors and biofilm promoting factors, and identifying key regulatory genes and pathways, and revealing the mechanism, adhesion effect and molecular mechanism of the biofilm formation of Shewanella putrefaciens. Furthermore, the purpose of regulating the formation of biofilms will beis achieved, which lays a theoretical foundation for the application and prevention of biofilms.