苏云金杆菌新菌株WZ-7的PCR-RFLP分析及生物活性研究

Analysis of cry-type gene by PCR-RFLP an d toxicity activity from Bacillus thuringiensis WZ-7

利用PCR -RFLP技术分析了自河北省土壤中分离的苏云金杆菌新菌株WZ - 7,结果表明该菌株含有cry1、cry2Ab、cry1Ia1型基因 ,其中cry1型基因的酶切片段类型不同于已发表的基因类型 ,有可能含有新的基因。SDS -PAGE分析结果出现 1 30、79、73、66、60、58kD左右的 6种晶体蛋白 ,毒素蛋白类型属于II型。室内生测结果显示 ,该菌株对重要的农业害虫棉铃虫、甜菜夜蛾、小菜蛾、菜青虫、玉米螟等均有较高的杀虫毒力。

Cry-type genes from a new Baci llus thuringiensis WZ-7 strain was isola ted from Hebei Province were identified by PCR-RFLP.PCR-RFLP was used to dete ct the cry-type gene from Bt strains The results showed it co ntain 3 types of ICPs genes:cry1-type,cry2Ab,cry1Ia1.The enzyme-cutting result of products is difference from that of published.Cry1 -type gene may be a kind of new gene.SDS-PAGE showed that the crysta l proteins were divid ed into 130,79,73,66,60,58 kD fragments.The bioassay in lab showed WZ-7 w as high toxicity against four lepidoptera pests:Helicoverpa armigera, Spodoptera exigua,Pieris rpae,Plutella xylostella,Ostrinia furnacalis.