A plasmid encoding a combination of mosquito-larvicidal genes from Bacillus thuringiensis subsp. israelensis and Bacillus sphaericus confers toxicity against a broad range of mosquito larvae when expressed in Gram-negative bacteria.
A recombinant plasmid harboring cry4A, cry4B and cry11A from Bacillus thuringiensis subsp. israelensis and binary toxin genes from Bacillus sphaericus has been constructed. The three cry genes were placed under the control of the cry4B promoter whereas the binary toxin gene was controlled by its native promoter. The expression of toxins in Escherichia coli harboring the resulting plasmid, p4BDA-5142, was investigated. Cry4B expression was highest compared to other toxins. Although the level of toxin expression was low compared with E. coli expressing single toxins, the recombinant E. coli strain harboring p4BDA-5142 exhibited broad range mosquito-larvicidal activity against all Aedes, Culex and Anopheles larvae. This work has shown that the development of the recombinant plasmid can be used to broaden the host range spectrum of the appropriate bacterial host for mosquito control.
Tanapongpipat
Sutipa
S
BIOTEC Central Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Phaholyothin Rd, Klong 1, Klongluang, Pathumthani 12120, Thailand. sutipa@biotec.or.th
Luxananil
Plearnpis
P
Promdonkoy
Boonhiang
B
Chewawiwat
Namchai
N
Audtho
Mongkon
M
Panyim
Sakol
S
D000330:Aedes / Q000254:growth & development; D000818:Animals; D000852:Anopheles / Q000254:growth & development; D001407:Bacillus / Q000235:genetics*; D001413:Bacillus thuringiensis / Q000235:genetics; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics* / Q000633:toxicity; D001427:Bacterial Toxins / Q000235:genetics* / Q000633:toxicity; D003001:Cloning, Molecular; D003465:Culex / Q000254:growth & development; D009033:Culicidae / Q000254:growth & development; D004731:Endotoxins / Q000235:genetics* / Q000633:toxicity; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D005798:Genes, Bacterial; D006460:Hemolysin Proteins; D007306:Insecticides; D007814:Larva / Q000254:growth & development; D009876:Operon; D010572:Pest Control, Biological / Q000379:methods; D010957:Plasmids / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000096:biosynthesis; D014169:Transformation, Bacterial
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; D011994:Recombinant Proteins; C046134:binB protein, Bacillus sphaericus; C030956:insecticidal crystal protein, Bacillus Thuringiensis