群体感应AHLs对温和气单胞菌体外致腐因子分泌的影响

摘要

Aeromonas sobria AS7 separated from spoilage turbot were used as test strain.The relationship between different treatment (the nutrition of substrate,symbiotic cultivation and adding different kind of AHLs) and the spoilage factors (siderophore,protase and biofilm) were further studied.The results showed that the secretion of siderophore was affected by medium quality,that could be secret at natural substrate such as skim milk,while could not be produced at synthetic medium.Addition of AHLs had a significant influence on the production of siderophore,wherein C8-HSL was affected significantly and the production of siderophore presented positive correlation with the increase AHLs (P ＜ O.05),while effect on C6-HSL was not significant (P ＞ 0.05).The production of siderophore of Pseudomonas fluorescens and Shewanella putrefaciens was obvious promoted when symbiotic cultivation with AS7.Adding AHLs could also promote the production of protase and biofilm,and present the positive correlation (P ＜0.05),which demonstrated that the AHLs could regulate the production of extracellular protease,siderophore and biofilm in AS7.%摘 要 以大菱鲆腐败菌温和气单胞菌(Aeromonas sobria,AS7)为研究对象,研究了不同处理方式(营养基质、共生培养和添加不同种类的AHLs)对温和气单胞菌的致腐因子(嗜铁素、胞外蛋白酶、生物被膜)产生情况的影响,结果表明,菌株AS7嗜铁素的分泌受到培养基质的影响,在脱脂牛奶等天然基质中可以大量分泌嗜铁素,而市售的合成培养基中不能分泌嗜铁素;AHLs的添加对嗜铁素的产生量有影响,其中,C8-HSL影响显著,随添加的增加,嗜铁素分泌量呈现正相关(P＜0.05),而C6-HSL影响不显著(P＞0.05);共生条件下,温和气单胞菌对荧光假单胞菌和腐败希瓦氏菌嗜铁素的分泌有明显促进作用;AHLs的添加可以促进温和气单胞菌胞外蛋白酶和生物被膜的产量,且呈现正相关(P＜0.05),说明AHLs对温和气单胞菌产生胞外蛋白酶、嗜铁素和生物被膜具有调控作用.