Engineering Bacillus thuringiensis Cyt1Aa toxin specificity from dipteran to lepidopteran toxicity
Por:
Torres-Quintero, Mary-Carmen, Gomez, Isabel, Pacheco, Sabino, Sanchez, Jorge, Flores, Humberto, Osuna, Joel, Mendoza, Gretel, Soberon, Mario, Bravo, Alejandra
Publicada:
21 mar 2018
Categoría:
Multidisciplinary
Resumen:
The Cyt and Cry toxins are different pore-forming proteins produced by Bacillus thuringiensis bacteria, and used in insect-pests control. Cry-toxins have a complex mechanism involving interaction with several proteins in the insect gut such as aminopeptidase N (APN), alkaline phosphatase (ALP) and cadherin (CAD). It was shown that the loop regions of domain II of Cry toxins participate in receptor binding. Cyt-toxins are dipteran specific and interact with membrane lipids. We show that Cry1Ab domain II loop3 is involved in binding to APN, ALP and CAD receptors since point mutation Cry1Ab-G439D affected binding to these proteins. We hypothesized that construction of Cyt1A-hybrid proteins providing a binding site that recognizes gut proteins in lepidopteran larvae could result in improved Cyt1Aa toxin toward lepidopteran larvae. We constructed hybrid Cyt1Aa-loop3 proteins with increased binding interaction to Manduca sexta receptors and increased toxicity against two Lepidopteran pests, M. sexta and Plutella xylostella. The hybrid Cyt1Aa-loop3 proteins were severely affected in mosquitocidal activity and showed partial hemolytic activity but retained their capacity to synergize Cry11Aa toxicity against mosquitos. Our data show that insect specificity of Cyt1Aa toxin can be modified by introduction of loop regions from another non-related toxin with different insect specificity. © 2018 The Author(s).
Filiaciones:
Torres-Quintero, Mary-Carmen:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Gomez, Isabel:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Pacheco, Sabino:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Sanchez, Jorge:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Flores, Humberto:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Osuna, Joel:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Mendoza, Gretel:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Soberon, Mario:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
Bravo, Alejandra:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico
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