title: Bacillus sphaericus Mtx1 and Mtx2 toxins co-expressed in Escherichia coli are synergistic against Aedes aegypti larvae.
abstract: Mtx1 and Mtx2 are mosquitocidal toxins produced by some strains of Bacillus sphaericus during vegetative phase of growth. Mtx1 from B. sphaericus 2297 shows higher toxicity against Culex quinquefasciatus larvae than to Aedes aegypti larvae whereas Mtx2 from B. sphaericus 2297 shows lower toxicity against C. quinquefasciatus than to A. aegypti larvae. To test synergism of these toxins against A. aegypti larvae, mtx1 and mtx2 genes were cloned into a single plasmid and expressed in Escherichia coli. Cells producing both Mtx1 and Mtx2 toxins exhibited high synergistic activity against A. aegypti larvae approximately 10 times compared to cells expressing only a single toxin. Co-expression of both toxins offers an alternative to improve efficacy of recombinant bacterial insecticides. There is a high possibility to develop these toxins to be used as an environmentally friendly mosquito control agent.
authors.affiliation: National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Paholyothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand.
authors.forename: Amporn
authors.initials: A
authors.lastname: Rungrod
authors.forename: Natalia Kristianti
authors.initials: NK
authors.lastname: Tjahaja
authors.forename: Sumarin
authors.initials: S
authors.lastname: Soonsanga
authors.forename: Mongkon
authors.initials: M
authors.lastname: Audtho
authors.forename: Boonhiang
authors.initials: B
authors.lastname: Promdonkoy
mesh_terms: D000330:Aedes / Q000187:drug effects*; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity*; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity*; D004357:Drug Synergism; D004926:Escherichia coli / Q000235:genetics; D007306:Insecticides / Q000633:toxicity*; D007814:Larva / Q000187:drug effects; D007928:Lethal Dose 50
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D007306:Insecticides; C099210:Mtx2 protein, Bacillus sphaericus