蛭弧菌BDE-1的生物特性及促进其蛭质体形成的研究  

Characterization of a Bdellovibrio-and-like organism strain BDE-1 for promoting its Bdelloplast formation

作　　者：李敏佳[1] 吴冰 韩红操[3] 蔡俊鹏[1] LI Min-Jia;WU Bing;HAN Hong-Cao;CAI Jun-Peng(College of Food Science and Engineering,South China University of Technology,Guangzhou,Guangdong 510640,China;Analysis and Testing Center,South China University of Technology,Guangzhou,Guangdong 510640,China;College of Biological Science and Engineering,South China University of Technology,Guangzhou,Guangdong 510006,China)

机构地区：[1]华南理工大学食品科学与工程学院,广东广州510640 [2]华南理工大学分析测试中心,广东广州510640 [3]华南理工大学生物科学与工程学院,广东广州510006

出　　处：《微生物学通报》2018年第8期1641-1650,共10页Microbiology China

基　　金：广东省科技计划公益项目(2016A020222002)~~

摘　　要：【背景】蛭弧菌是众多海洋益生菌中的一类较新成员,应用前景十分广阔。但由于蛭弧菌特殊的繁殖方式和周期,它的应用效果受寄生宿主特性和生物活性的影响,因而优选寄生宿主,维持或者提高蛭弧菌微生态制剂的应用活性是关键。【目的】筛选出能够裂解枯草芽孢杆菌的蛭弧菌,以增进其益生性能;研究提高蛭弧菌的蛭质体密度,以利于保存。【方法】从海南取回海泥样后,以枯草芽孢杆菌作为宿主菌,通过稀营养肉汤(Dilute nutrient broth,DNB)双层平板法分离获得蛭弧菌,并对目标菌株进行透射电镜形态鉴定和16S rRNA基因序列分析;然后进行生物学特性研究,同时开展氨苄青霉素、吲哚、Ca^(2+)和Mg^(2+)影响蛭质体形成的研究。【结果】分离出一株以枯草芽孢杆菌作为宿主的蛭弧菌并命名为BDE-1,其最适温度、盐度和pH分别为25℃、2.0%和7.0;BDE-1可裂解24株试验菌,占总试验菌株数(28株)的85.7%,其中对试验弧菌(13株)的裂解率达92.3%;吲哚、氨苄青霉素、Ca^(2+)和Mg^(2+)4种因子对BDE-1蛭质体的形成均有促进作用,其中吲哚和Ca^(2+)的促进作用显著。【结论】研究结果不仅为蛭弧菌寄生宿主的优化选择提供了可行性解决思路,而且为维持或提高蛭弧菌微生态制剂的应用活性提供了理论依据。[Background] As a relatively new member of marine probiotics, Bdellovibro-and-like organisms（BALOs） have a wide application prospect. However, because of BALOs＇ special reproductive mode and cycle, the pratical application of BALOs is greatly affected by their parasitic host characteristics and biological activities. Therefore, selecting appropriate parasitic hosts and maintaining the activity of BALOs preparation are very important for BALOs＇ application. [Objective] To isolate a strain of BALOs which can use gram-positive probiotics Bacillus subtilis as host, and increase its Bdelloplast concentration in the culture for storage. [Methods] Bacillus subtilis was used as host bacterium to isolate BALOs from sea mud samples from Hainan by DNB（Dilute nutrient broth） double plate method. Transmission electron microscope and partial 16 S rRNA gene sequence analysis were conducted to identify the Bdellovibrio strain, and its biological characteristics and lysis spectrums were studied. In addition, the effects of ampicillin, indole, Ca^2＋ and Mg^2＋ on the formation of bdelloplast were researched. [Results] A strain of BALOs（named BDE-1） which could prey on Bacillus subtilis was isolated and identified successfully. The optimal temperature, salinity and pH for BDE-1 were 25 ℃, 2.0% and 7.0 respectively. Lysis experiments on 28 pathogenic or potential pathogenic strains showed that BDE-1 lysed 24 strains, corresponding to 85.7% of lysis rate. For the 13 strains of tested vibrios, its lytic rate was as high as 92.3%. While all four factors（indole, ampicillin, Ca^2＋ and Mg^2＋） promoted bdelloplast formation, the promotion effect of indole and Ca^2＋ was more significant. [Conclusion] This study not only provided a feasible solution for the optimal selection of parasitic hosts of Bdellovibro, but also provided a theoretical basis for the maintenance or enhancement of the application of Bdellovibro probiotic preparation.

关 键 词：蛭弧菌 蛭质体形成 分离和鉴定 吲哚 氨苄青霉素 钙镁离子 

分 类 号：Q93[生物学—微生物学]