鱼源假单胞菌群体感应信号分子与腐败特性相关关系的研究

 【目的】革兰氏阴性菌通过产生N-酰基-高丝氨酸内酯（AHLs）类信号分子，以密度依赖的方式调控某些生理特性的表达，即群体感应（QS）现象。假单胞菌是一种导致蛋白类食品腐败的重要腐败细菌。本研究的目的是确定假单胞菌群体感应信号分子与腐败特性的关系。【方法】利用AHLs检测菌对3株假单胞菌AHLs产生情况进行检测，并通过AHLS降解菌株对所产生的AHLs进行降解。【结果】3株菌均产生AHLs信号分子；菌株FML05-1、FML05-2至少产生两种AHLs分子，二者所产生的主要信号分子是N-3-氧代-辛酰基-高丝氨酸内酯（N-3-oxo-C8-HSL）；FML05-2与降解AHLs的菌株共同培养，发现嗜铁素的产量与蛋白酶活性明显下降。【结论】FML05-2嗜铁素的产生和蛋白酶活性与AHLs有关。为以干扰腐败细菌群体感应为靶点的食品防腐保鲜策略提供研究基础。

Research on Relationship Between Quorum Sensing Signal Molecules and Characteristics of Spoilage in Pseudomonas spp. Isolated from Fish

ObjectiveThe study looked at gram-negative bacteria,which regulated the expression of some traits in a cell density-dependent manner by producing the N-acyl-homoserine lactones (AHLs) signal molecules,(i.e.,quorum sensing). Pseudomonas is an important bacteria that caused spoilage of proteinaceous foods. The aim was to research on relationship between quorum sensing signal molecules and characteristics of spoilage in Pseudomonas.MethodThe AHLs were detected in three Pseudomonas strains by the AHLs biosensor and degraded by the AHLs degrader strain.ResultThe three strains all produced the AHL signal molecules; the strains FML05-1and FML05-2 produced two types of AHLs at least and the N-3-oxo-octanoyl-homoserine lactone was the predominant signal molecules. The production of siderophore and proteinase in FML05-2 were reduced by co-incubation with AHL degrader strain.ConclusionThere was a relationship between the production of siderophore,proteinase activity and AHLs. This study lays the foundation for new strategies of food preservation based on interfering in quorum sensing of spoilage bacteria.