Site-directed mutations in the third domain of Bacillus thuringiensis delta-endotoxin CryIAa affect its ability to increase the permeability of Bombyx mori midgut brush border membrane vesicles.
AUTOR(ES)
Wolfersberger, M G
RESUMO
A series of mutant Bacillus thuringiensis CryIAa delta-endotoxin proteins was prepared by replacing the first, second, and last arginine residues of the conserved third-domain sequence, R-521 YRVRIR-527, with other amino acids. The stable mutant proteins were bioassayed against Bombyx mori larvae and found to all be approximately half as active as wild-type CryIAa. The toxins were also tested by means of a light-scattering assay for their ability to increase permeability of larval B. mori midgut brush border membrane vesicles. Three of the mutant toxins were as active as the wild-type toxin in the vesicle permeability assay.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=167797Documentos Relacionados
- Identification of amino acid residues of Bacillus thuringiensis delta-endotoxin CryIAa associated with membrane binding and toxicity to Bombyx mori.
- Site-directed mutations in a highly conserved region of Bacillus thuringiensis delta-endotoxin affect inhibition of short circuit current across Bombyx mori midguts.
- Single amino acid changes in domain II of Bacillus thuringiensis CryIAb delta-endotoxin affect irreversible binding to Manduca sexta midgut membrane vesicles.
- Location of the Bombyx mori specificity domain on a Bacillus thuringiensis delta-endotoxin protein.
- Two Different Bacillus thuringiensis Delta-Endotoxin Receptors in the Midgut Brush Border Membrane of the European Corn Borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Pyralidae)