Elleuch J., Jaoua S., Ginibre Carole, Chandre Fabrice, Tounsi S., Zghal R. Z. (2016). Toxin stability improvement and toxicity increase against dipteran and lepidopteran larvae of Bacillus thuringiensis crystal protein Cry2Aa. Pest Management Science, 72 (12), p. 2240-2246. ISSN 1526-498X.
Titre du document
Toxin stability improvement and toxicity increase against dipteran and lepidopteran larvae of Bacillus thuringiensis crystal protein Cry2Aa
Elleuch J., Jaoua S., Ginibre Carole, Chandre Fabrice, Tounsi S., Zghal R. Z.
Source
Pest Management Science, 2016,
72 (12), p. 2240-2246 ISSN 1526-498X
BACKGROUNDBacillus thuringiensis -endotoxins are the most widely used biopesticides for controlling economically important crop pests and disease vectors. Improving their efficacy is of great benefit. Here, an improvement in Cry2Aa-endotoxin toxicity was attempted via a cry gene over expression system using P20 from B. thuringiensis israelensis. RESULTSThe coexpression of Cry2Aa with P20 resulted in a seven fold increase in its production yield in B. thuringiensis. Generated crystals proved to be significantly more toxic (505.207 mu gg(-1), 1.99mgL(-1) and 1.49mgL(-1)) than the P20-lacking control (720.78 mu gg(-1), 705.69mgL(-1) and 508.51mgL(-1)) against Ephestia kuehniella, Aedes aegypti and Culex pipiens larvae respectively. In vitro, processing experiments revealed a P20-mediated protection of Cry2Aa against degradation under larval gut conditions. Thus, P20 could promote the maintenance of a tightly packaged conformation of Cry2Aa toxins in the larval midgut upon correct activation and binding to its membrane receptors. CONCLUSIONBased on their resistance against excessive proteolysis, Cry2Aa-endotoxins, produced in the presence of P20, could be considered as a successful control agent for E. kuehniella and an effective alternative for mosquito control, implying its possible exploitation in pest management programmes.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020]
;
Entomologie médicale / Parasitologie / Virologie [052]
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Sciences du monde végétal [076]
;
Biotechnologies [084]
