杀虫防菌Bt工程菌的构建

Research on construction and insecticidal and germproof bioactivity of recombinant bacillus thuringensis

N-乙酰高丝氨酸内酯(N-acyl-homoserine lactones,AHLs)是革兰氏阴性细菌胞间通讯的信号分子,能够调控许多植物病原菌的致病基因的表达,但如果内酯酶将其水解,则会影响病原菌的致病活性,植物就不会染病。苏云金芽孢杆菌(Bacillus thuringiensis,Bt),作为生物杀虫剂已有多年使用的历史,本研究通过生物技术手段成功地构建了携带信号分子AHL水解酶基因的穿梭载体pHTss10304,并转入到具有Bt中,构建成工程菌Bt24、工程菌Bt33、工程菌Bt34和工程菌Bt36。通过设计,实现了Bt工程菌的多功能改造,为BT工程菌的应用提供了更为广阔的空间,为生物防治菌的开发现有菌剂提供了新的思路。

N-acyl-homoserine lactones（AHLs）,which are signal molecules in quorum-sensing systems,can regulate to express virulence genes of lots of bacterial pathogens.However,bacterial pathogens will not manifest their cellular behaviour if AHLs cannot reach a threshold concentration.Gene of AHL hydrolase was successfully inserted in shuttle vector pHT304between Bt and E.coli.The plasmid pHTsss10304has been constructed by the means of biotechnology,and shift to bacillus thuringensis which is a insecticidal bacteria.Recombinant bacillus thuringensis 24、33、34and 36（Bt24、Bt33、Bt34、Bt36）was acquired.In virtue of Chromobacterium violaceum CV026and plant potato,the results show that recombinant Bt can express hydrolase protein greatly and behave great resistance to E.CC.And recombinant Bt have no effect on their insect disinfestation.