Stability,oviposition attraction,and larvicidal activity of binary toxin from <Emphasis Type="Italic">Bacillus sphaericus</Emphasis> expressed in <Emphasis Type="Italic">Escherichia coli</Emphasis> |
| |
Authors: | Luciano da Silva Pinto Relber Aguiar Gonçales Fabricio Rochedo Conceição Paula Ferreira Knabah Sibele Borsuk Vinicius Farias Campos Francisco Vassiliepe Arruda Fabio Pereira Leivas Leite |
| |
Institution: | Centro de Desenvolvimento Tecnológico, Núcleo Biotecnologia, UFPel, Campus Universitário, s/n, Caixa Postal 354, Pelotas, RS, 96010-900, Brazil. dmpluc@gmail.com |
| |
Abstract: | Bacillus sphaericus produces a two-chain binary toxin composed of BinA (42 kDa) and BinB (51 kDa), which are deposited as parasporal crystals during sporulation. The toxin is highly active against Culex larvae and Aedes and Anopheles mosquitoes, which are the principal vectors for the transmission of malaria, yellow fever, encephalitis, and dengue. The use of B. sphaericus and Bacillus thuringiensis in mosquito control programs is limited by their sedimentation in still water. In this study, the binA and binB genes were cloned and the recombinant BinAB protein was expressed in three strains of Escherichia coli. These recombinant strains were used in a toxicity assay against Culex quinquefasciatus larvae. The highest expression level was achieved when both proteins were expressed in a single operon construct. The BinAB protein expressed in the E. coli Arctic strain showed higher larvicidal activity than either of the recombinant proteins from the E. coli Ril or pLysS strains. Furthermore, it had the highest oviposition attraction (49.1%, P?0.05). These data suggest that biologically active recombinant BinA and BinB toxins might be useful in mosquito control programs, delivered by inactivated bacterial cells or in traps. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|