摘要
将cry1Ac1 0基因和苏云金芽胞杆菌的复制起始区连接在一起 ,并在其两侧按相同方向各连接一个来自苏云金芽胞杆菌转座子Tn4430的解离位点 ,构成转移单位。再将革兰氏阳性细菌的抗性标记基因和大肠杆菌克隆载体 pUC1 9与之连接 ,获得含cry1Ac1 0基因的解离载体pBMB80 1。将其转化苏云金芽胞杆菌无晶体突变体 ,再导入含解离酶基因的辅助质粒 pBMB1 2 0 0。在解离酶作用下 ,两个解离位点间发生重组 ,消除基在操作中的抗性标记基因等非必需基因片段 ,获得仅保留有完整cry1Ac1 0基因和来自苏云金芽胞杆菌质粒复制起始区 ,在无抗生素选择压力下能稳定遗传的重组质粒pBMB80 1B。
A new resolution vector with cry1Ac10 gene based on TnpⅠ mediated site specific recombination system of Bacillus thuringiensis(Bt) transposon Tn4430 was developed. The gene cry1Ac10 , encoding a protoxin against plutella xylostella larvae, and the gene ori1030, from a plasmid of wide type Bacillus thuringiensis, were inserted into two copy sets of RES sites, named pBMB801. When pBMB801 was introduced into crystal negative Bt host BMB171, antibiotic resistance genes and other non Bt DNA can be selectively eliminated. This recombinant plasmid was found very stable without antibiotic selection. The resulting strain only contained Bt DNA and is free of antibiotic resistance genes. This strategy should facilitate regulatory approval for its developemnt as a commercial biopesticide.
出处
《微生物学报》
CAS
CSCD
北大核心
2000年第3期264-269,共6页
Acta Microbiologica Sinica
基金
国家高技术研究发展计划 ( 863计划 )资助!课题 ( 1 0 1 0 3 0 1 0 1 )
