为了探索ERIC-PCR技术在苏云金芽胞杆菌和蜡状芽胞杆菌的鉴定及分型中的应用价值,本研究采用PCR方法初步检测苏云金芽胞杆菌杀虫晶体蛋白基因的组成,并对苏云金芽胞杆菌和蜡状芽胞杆菌的总DNA进行ERIC-PCR扩增,分析ERIC-PCR指纹图谱的特点并采用NTSYS2.10软件对其进行聚类。结果显示,各菌株的ERIC指纹图谱表现出不同程度的多态性,但图谱与菌株所含cry基因的类型存在一定的相关性。聚类分析结果显示,含有相同或相近cry基因类型的Bt菌株在进化树上趋向聚为一类,而不含cry基因的蜡状芽胞杆菌趋向于与不含cry基因的Bt菌株聚为一类或单独聚类。若在多种模式菌株的参考下,该方法可用于苏云金芽胞杆菌的初步鉴定和分型。

In order to assess the application value of ERIC-PCR method in identification and type of Bacillus thuringiensis and Bacillus cereus strains,the crystal protein genes were preliminarily detected in B.thuringiensis strains by PCR. And the total DNA of B. thuringiensis and B. cereus strains were amplified by ERIC-PCR primers. Then the ERIC fingerprints were analyzed and clustered by NTSYS 2.10. The results showed polymorphism at different level present in the ERIC-PCR fingerprint, which has a certain correlation with the cry gene type in the strain. Clustering analysis results showed B. thuringiensis strains carried same or similar cry gene type were clustered one group in phylogenetic tree, and B. cereus strains lack cry genes were clustered one group with the B.thuringiensis strains lack cry genes or alone. This method can be used for the preliminary identification and classification of B.thuringiensis, if multiple model strains were used as reference strains.