基因工程杀蚊幼蓝藻的研究

Studies on Genetically Engineered Larvicidal Cyanobacterium

应用基因工程手段研制杀蚊幼蓝藻,是解决苏云金杆菌和球形芽孢杆菌等短持效问题的途径之一。但国际上基因工程蓝藻的毒效一直限于较低水平,甚至需要破碎细胞才能检测到对蚊幼虫的毒杀作用。本文将球形芽孢杆菌毒素基因装配鱼腥藻启动子后,转移入鱼腥藻进行表达,所得基因工程株对蚊幼虫具有十分显著的毒效,对淡色库蚊幼虫24h半致死浓度为2.31×10~4细胞/ml;其对淡色库蚊、中华按蚊、白纹伊蚊幼虫的毒效依次递减,这与球形芽孢杆菌相似。由于鱼腥藻易培养、生态适应性广等,可望成为蚊虫特效控制的新型武器。

Expression of toxin genes of high toxic Bacillus in cyanobacteria is a potenial way to reach prolonged mosquito control. But for their low toxicity, the genetically engineered cyanobacteria can not be practically used hitheto, and in most reports, the recombinant cells need lysate for toxicity essays. In. this research, high larvicidal activity of recombinant Anabaena was developed by expressing the toxin genes of B. sphaericus from an Anabaena promoter. LC_(50)(24h.) of the larvicidal cyanobacterium to larvae of Culex pipiens was 2.31×10~4 cells/ml, and its practical use under outdoor conditions was demonstrated. Similar to B. sphaericus, its toxicity to larvae of Culex pipiens. Anopheles sinensis and Aedes albopictus decrvases in order. For its simple growth requirements and wide ecological adaptations, the larvicidal Anabaena might become a new weapon for prolonged control on mosquito.