Con A修饰型抗菌肽脂质体对单增李斯特菌生物被膜的靶向作用及机制研究

项目名称： Con A修饰型抗菌肽脂质体对单增李斯特菌生物被膜的靶向作用及机制研究

项目编号： No.31501578

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 农业科学

项目作者： 唐文婷

作者单位： 青岛农业大学

项目金额： 20万元

中文摘要： 单增李斯特菌是一种自然界较为常见的食源性致病菌，在食品加工、储运过程中可黏附于食品、设备表面形成生物被膜。被膜菌具有更强的抗逆性，难以彻底清除，危及食品安全。抗菌肽能克服传统生物被膜控制方法的局限性，有望成为潜在的替代手段。本研究在证实鳀鱼抗菌肽脂质体具有抗单增李斯特菌生物被膜活性的基础上，基于刀豆球蛋白A(Concanavalin A, Con A)与被膜胞外多聚物中糖单元的特异性亲和作用，利用Con A对该抗菌肽脂质体进行表面修饰，实现脂质体的主动靶向传递，提高其在生物被膜表面的作用浓度。考察不同制备条件对Con A修饰型抗菌肽脂质体理化性质和抗被膜活性的影响；建立表面单层覆盖模型，分析抗菌肽脂质体与被膜的靶向性相互作用；通过研究抗菌肽脂质体对单增李斯特菌细胞表面黏附性及群体感应相关基因的影响，明确该脂质体对单增李斯特菌生物被膜的调控机制，为实现食源性致病菌生物被膜的有效控制奠定基础。

中文关键词： 生物被膜；单增李斯特菌；抗菌肽；脂质体；机制

英文摘要： Listeria monocytogenes is a food-borne pathogen which is widely distributed in the environment. L. monocytogenes is capable of attaching to the surfaces of food and equipments, and forming biofilm in food processing, storage and transportation process. The cells in the biofilm are more resistant and more difficult to completely remove, which endangers food security. Antimicrobial peptides are expected to become potential alternatives because they can overcome the limitations of traditional biofilm control methods. Based on our previous result that the anchovy antibacterial peptide liposome exhibited anti- L. monocytogenes biofilm activity, the liposome is proposed to be surface-modified by concanavalin A (Con A) according to the specific affinity interaction between Con A and the carbohydrates in the extracellular polymers of the biofilm, in order to achieve active targeting delivery and improve the peptide concentration on the surface of the biofilm. The objectives of the research are as follows: to find the effect of preparation condition on the physicochemical properties and activities of the antimicrobial peptide liposome; to establish the surface monolayer coverage model to analyze the targeted interaction between the liposome and the biofilm; to investigate the influence of the liposome on the surface adhesion and the expression of quorum sensing-related genes of the Listeria cells; to reveal the L. monocytogenes biofilm control mechanism of the Con A modified antimicrobial peptides liposome. The results will lay the foundation for the realization of effective control of food-borne pathogens biofilm.

英文关键词： biofilm;Listeria monocytogenes;antibacterial peptide;liposome;mechanism