双歧杆菌与乳杆菌原生质体的融合及筛选

目的：通过双歧杆菌与乳杆菌的原生质体融合构建耐氧双岐杆菌，以解决双岐杆菌制剂开发中始终存在的“活菌数低”和存活时间短等问题。方法：采用不同浓度的Mutanolysin分别制备长岐杆菌和保加利亚乳杆菌的原生质体，在电场作用下诱导长双岐杆菌原生质体和经56℃热灭活30min的保加利亚乳杆菌原生质体融合，并在双层再生培养基上筛选融合菌株。结果：成功地构建出几种较为稳定的兼具长双岐杆菌和保加利亚乳杆菌生物学特性的融合菌株；其中融合株F2具有良好的耐氧性；且能在有氧、CO2条件下良好生长。结论：通过原生质体融合技术能改良双歧杆菌的严格厌氧特性，有利于对双岐杆菌的开发和应用。

Fusion and Identification in Protoplast of Bifidobacterium and Lactobacillus

Objectives: Bifidobacterium ,which are obligate anaerobic microorganisms,soon die in the air.For this,it is inconvenient or disadvantageous to exploitation and applications of Bifidobacterium .Utilizing the technology of protoplast fusion,facultative Lactobacillus 's aerotolerant gene was integrated into Bifidobacterium 's chromosomes randomly to improve their tolerance of aerobic life or change their obligate anaerobic character.Methods:Protoplasts of Bifidobacterium and Lactobacillus were performed by lytic enzymes Mutanolysin respectively.Then protoplast fusion in Bifidobacterium and Lactobacillus were completed through electric field.Results:Fusant strains between Bifidobacterium and Lactobacillus were obtained successfully.Among these,F2 can grow well in the air or CO 2.Conclusion:Oxygen-resistence Bifidobacterium can be builded through the technology of protoplast fusion in Bifidobacterium and Lactobacillus .In addition,fusants are more convinent to exploitation and applications of Bifidobacterium in the near future.