Kinetics of pore formation by the Bacillus thuringiensis toxin Cry1Ac
نویسندگان
چکیده
منابع مشابه
Membrane pore architecture of a cytolytic toxin from Bacillus thuringiensis.
To investigate the membrane pore structure of Cyt2Aa1 toxin from Bacillus thuringiensis, 14 single-cysteine substitutions of the toxin were constructed. Five of these mutants (L172C, V186C, L189C, E214C and L220C) yielded characteristic products when processed by proteinase K; other mutants were degraded by this enzyme. Mutants that yielded characteristic proteolysed products and wild-type toxi...
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A cadherin-like protein has been identified as a putative receptor for Bacillus thuringiensis (Bt) Cry1Ac toxin in Helicoverpa armigera and plays a key role in Bt insecticidal action. In this study, we produced a fragment from this H. armigera Cry1Ac toxin-binding cadherin that included the predicted toxin-binding region. Binding of Cry1Ac toxin to this cadherin fragment facilitated the formati...
متن کاملProtease inhibitors fail to prevent pore formation by the activated Bacillus thuringiensis toxin Cry1Aa in insect brush border membrane vesicles.
To investigate whether membrane proteases are involved in the activity of Bacillus thuringiensis insecticidal toxins, the rate of pore formation by trypsin-activated Cry1Aa was monitored in the presence of a variety of protease inhibitors with Manduca sexta midgut brush border membrane vesicles and by a light-scattering assay. Most of the inhibitors tested had no effect on the pore-forming abil...
متن کاملIdentification of residues in domain III of Bacillus thuringiensis Cry1Ac toxin that affect binding and toxicity.
Alanine substitution mutations in the Cry1Ac domain III region, from amino acid residues 503 to 525, were constructed to study the functional role of domain III in the toxicity and receptor binding of the protein to Lymantria dispar, Manduca sexta, and Heliothis virescens. Five sets of alanine block mutants were generated at the residues (503)SS(504), (506)NNI(508), (509)QNR(511), (522)ST(523),...
متن کاملEffects of entomopathogenic nematodes on evolution of pink bollworm resistance to Bacillus thuringiensis toxin Cry1Ac.
The evolution of resistance by pests can reduce the efficacy of transgenic crops that produce insecticidal toxins from Bacillus thuringiensis (Bt). However, fitness costs may act to delay pest resistance to Bt toxins. Meta-analysis of results from four previous studies revealed that the entomopathogenic nematode Steinernema riobrave (Rhabditida: Steinernematidae) imposed a 20% fitness cost for ...
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ژورنال
عنوان ژورنال: Biochimica et Biophysica Acta (BBA) - Biomembranes
سال: 2007
ISSN: 0005-2736
DOI: 10.1016/j.bbamem.2007.02.013