Publications des scientifiques de l'IRD

Zghal R. Z., Frikha F., Elleuch J., Darriet Frédéric, Chandre Fabrice, Jaoua S., Tounsi S. (2019). The combinatory effect of Cyt1Aa flexibility and specificity against dipteran larvae improves the toxicity of Bacillus thuringensis kurstaki toxins. International Journal of Biological Macromolecules, 123, p. 42-49. ISSN 0141-8130.

Titre du document
The combinatory effect of Cyt1Aa flexibility and specificity against dipteran larvae improves the toxicity of Bacillus thuringensis kurstaki toxins
Année de publication
2019
Type de document
Article référencé dans le Web of Science WOS:000456760100006
Auteurs
Zghal R. Z., Frikha F., Elleuch J., Darriet Frédéric, Chandre Fabrice, Jaoua S., Tounsi S.
Source
International Journal of Biological Macromolecules, 2019, 123, p. 42-49 ISSN 0141-8130
Cyt1A98 is a novel cytolytic protein, from BUPM98 Bacillus thuringiensis strain, characterized by its synergistic activity with B. thuringiensis kurstaki toxins against lepidopteran larvae. In this study, we evidenced that Cyt1A98 improves the toxicity of B. thuringiensis kurstaki toxins against Aedes aegypti larvae. In fact, the strain BNS3pHTcyt1A98 exhibited a larvicidal activity of about 849-fold of that of BNS3pHTBlue against A. aegypti. The molecular and biochemical characterizations, of cyt1A98 gene and its product, were achieved. Cyt1A98 had an LC50 value of about 126.56 mg l(-1) against A. aegypti larvae. Compared to Cyt1Aa of B. thuringiensis israelensis, Cyt1A98 amino acid sequence harbours three substitutions of three conserved amino adds among Cyt1Aa family members (Ser42Pro, Pro82A1a, Met188Thr). The Cyt1A98 protein structural analysis evidenced more flexibility than Cyt1Aa. According to the high fluctuation observed for the residue Pro42, the amino acid at position 42 is implicated in the flexibility property of Cyt1Aa especially for the alpha C and alpha D helices, involved in the penetration into the cell membrane. The toxicity improvement could be probably due to the higher flexibility combined with the specific affinity toward dipteran larvae. The Cyt1A/B. thuringiensis kurstaki Cry toxins model provides a potential molecular genetic strategy for an efficient bioinsecticide.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Entomologie médicale / Parasitologie / Virologie [052] ; Biotechnologies [084]
Localisation
Fonds IRD [F B010074941]
Identifiant IRD
fdi:010074941
Contact