在乳酸菌和酵母菌的共培养过程中，营养上的相互需求只是其共生基础的一部分。某些菌种经常作为环境中的刺激因素触发特定菌种的群体感应现象，实现对其自身代谢、基因转录及很多重要生理功能的调控。这对乳酸菌群体感应现象的研究以及酵母菌与乳酸菌在共培养中的互作机理打开了新的思路。本项目从乳酸菌的LuxS/AI-2系统出发，将酵母菌当作环境中的刺激因素，比较乳酸菌单菌培养、外源添加AI-2、与酵母菌共培养三者之间核酸和蛋白表达的差异，从而得到乳酸菌与酵母菌共培养中乳酸菌在代谢和实现某些重要生理功能途径上关键蛋白的差异，分析酵母菌对乳酸菌生理功能的影响；同时通过与外源添加AI-2信号分子的乳酸菌蛋白变化的比较，寻找其与酵母菌共培养蛋白表达的相关性，得出LuxS/AI-2群体感应系统在共培养过程中扮演的角色以及起到的调控作用。期望通过外源添加信号分子AI-2，高效便捷的实现对乳酸菌某些重要生理功能的调控。

During the process of lactic acid bacteria (LAB) co-culturing with yeast, the nutritional need is just basic one part of the symbiosis. As the environmental stimulating factors, some specific strains achieve their metabolism, operate gene transcription and regulate many important physiological functions by utilizing quorum sensing (QS). This phenomenon gives us new perspective when we investigate the QS of LAB and the interactions between LAB and the yeast under the condition of co-culture. Using yeast as a stimulating factor of the environment in this project, starting from LAB LuxS/AI-2 system, we will compare the protein and nucleic acid expression among LAB single strain culture (Group 1), and co-culture with yeast (Group 2) and add exogenous signal AI-2 to LAB (Group 3). This comparison aims to obtaining some significant physiological function differences on Key-protein, and analyzing the yeast effect on the physiological functions of LAB in the process of co-culture. Moreover, we compared group 2 and 3 to seek the protein expression co-relationship, then we can ascertain the role which LuxS/AI-2 plays in QS co-culture. The quintessence of the project is to efficiently regulate some physiological functions of LAB by exogenously adding AI-2.