摘要： 对我室所保存的18株含cry7类基因的菌株进行晶体形状、生物活性和蛋白型基因型等进行分析.结果表明:这些菌株能产生菱形、小菱形和不规则形伴胞晶体,SDS-PAGE检测主要蛋白的分子量是130 kDa,PCR扩增得到1 300 bp条带.对马铃薯瓢虫二龄幼虫的生物活性测定结果表明,菌株WZ-9具有很高的杀虫率,72 h校正死亡率达到了93.1%;菌株WCG-10活性次之,72 h校正死亡率达到.8%,而其他菌株杀虫活性低或没有活性.对杀虫活性最高的WZ-9菌株扩增全长基因,得到cry7Ab3基因(GenBank Number:BI 1015188).

关键词: 苏云金芽胞杆菌, cry7基因, 马铃薯二十八星瓢虫

Abstract: Based on PCR amplification using universal primers，18 strains of Bt containing cry7 gene were obtained and analysis further about crystal shape，bioassay，toxin protein and gene type. Bi-pyramidal and irregular crystal shape were presented in these strains. Toxin from Bt strain appeared to contain a prominent protein band at a molecular weight of 130 kDa on SDS-PAGE. Genotypic investigations showed that these strains possessed the cry7 gene， and the amplified fragments were 1 300 bp. Bioassay results showed that the WZ-9 strain was only harmful to larvae of Henosepilachna vigintioctomaculata，c orrected mortality was 93. 1% at 72 h. And the strain WCG-10 showed weak toxicity，corrected mortality was 44. 8% at 72 h. Other strains were no toxicity against this insect. The full length toxin gene，cry7Ab3，was amplified and submitted to the committee of Bt toxin nomenclature (GenBank Number: BI1015188).

Key words: Bacillus thuringiensis, cry7 gene, Henosepilachna vigintioctomaculata

中图分类号: 

• Q78