南方医科大学学报2017，Vol.37Issue(6)：750-754,5.DOI:10.3969/j.issn.1673-4254.2017.06.06
表达蝎毒素AaIT或苏云金杆菌毒素Cyt2Ba的大肠埃希菌杀蚊幼活性及增效剂型测试
Larvicidal activity of recombinant Escherichia coli expressing scorpion neurotoxin AaIT or B.t.i toxin Cyt2Ba against mosquito larvae and formulations for enhancing the effects
摘要
Abstract
Objective To assess the larvicidal effects of recombinant Escherichia coli expressing scorpion neurotoxin AaIT or Bacillus thuringiensis subsp israelensis (B.t.i) toxin Cyt2Ba against the second instar larvae of Culex pipiensquinquefasciatus and Aedes albopictus and compare different formulations for their larvicidal effects. Methods The AaIT-or Cyt2Ba-coding sequences were cloned into pET28a(+) and the recombinant plasmids were transformed into E. coli BL21(DE3). After induction with IPTG, the recombinant proteins expressed by the recombinant E. coli were detected and identified by SDS-PAGE and Western blotting, respectively. The larvicidal activity of the bacterial suspension was tested at different concentrations against mosquitoes. The effective engineered bacteria were prepared into dry powder with different formulations, and their larvicidal activity was tested. Results AaIT and Cyt2Ba proteins were successfully expressed in E. coli. The recombinant AaIT protein showed no virulence to the mosquito larvae. The suspension of the recombinant E. coli expressing Cyt2Ba protein exhibited a stronger killing effect on Aedes albopictus larvae than on Culex pipiens quinquefasciatus larvae at 48 h (P<0.001) with LC50 of 3.00× 106 cells/mL and 1.25 × 107 cells/mL, respectively. The dry powder of the engineered bacteria formulated with yeast extract, wheat flour or white pepper powder at the mass ratio of 1:1 showed the strongest killing effect on mosquito larvae (P=0.044), and the formulation with white pepper powder produced a stronger killing effect than formulations with yeast extract or wheat flour (P=0.002). Conclusion The B.t.i Cyt2Ba protein expressed in E. coli BL21(DE3) shows a good larvicidal activity against mosquitoes, and appropriate formulations of the engineered bacteria can enhance its efficiency in mosquito control.关键词
AaIT/Cyt2Ba/白纹伊蚊/致倦库蚊/苏云金杆菌毒素Key words
AaIT/Cyt2Ba/Aedes albopictus/Culex pipiens quinquefasciatus/Bacillus thuringiensis subsp israelensis引用本文复制引用
邓胜群,邓茗芝,陈嘉婷,郑丽兰,彭鸿娟..表达蝎毒素AaIT或苏云金杆菌毒素Cyt2Ba的大肠埃希菌杀蚊幼活性及增效剂型测试[J].南方医科大学学报,2017,37(6):750-754,5.基金项目
国家自然科学基金(81271866,81572012) （81271866,81572012）
广东省高等学校珠江学者岗位计划(2014) （2014）
广东省自然科学基金重点项目(2016A030311025) （2016A030311025）
广州市健康医疗协同创新重大专项(201604020011) Supported by National Natural Science Foundation of China (81271866, 81572012). （201604020011）
