Interaction between functional domains of Bacillus thuringiensis insecticidal crystal proteins

Rang Cécile, Vachon Vincent, De Maagd R., Villalon M., Schwartz Jean Louis, Bosch D., Laprade Raynald. 1999. Interaction between functional domains of Bacillus thuringiensis insecticidal crystal proteins. Applied and Environmental Microbiology, 65 (7) : 2918-2925.

Autre titre : Etude des interactions entre les domaines fonctionnels des protéines insecticides cristalines de Bacillus thuringiensis

Résumé : Interactions among the three structural domains of Bacillus 1huringiensis Cn.l toxins %~ere investigated by functional analysis of chinieric proteins. Hybrid genes were prepared by exchanging the regions coding for either domain 1 or domain III among CrylAb, Cn,lAc, CrylC, and CrylE. The activity of the purified trypsinactivated chimeric toxins was evaluiated by testing their effects on the viability and plasma membrane permeability of Sf9 cells. Among the parental toxins, only CrylC was active against these cells and only chimeras possessing domain II from CrylC were functional. Combination of domain 1 from CrylE Niith domains Il and III from CrylC, however, resulted in an inactive toxin, indicating that domain II from an active toxin is necessary, but not sufficient, for activity. Pores formed by chimeric toxins in which domain I was frorn Cr31M or CrylAc were slightly smaller than those formed by toxins in which domain I was from CrylC. The properties of the pores formed by the chimeras are therefore likely to result froin an interaction between domain I and domain II or 111. Domain III appears to modulate the activity of the chimeric toxins: combination of domain 111 from CrylAb with domains 1 and II of CrylC gave a protein which was more strongly active than CrylC.

Mots-clés Agrovoc : Bacillus thuringiensis, toxine bactérienne, pesticide bactérien, insecticide, fonction physiologique, interaction génique

Classification Agris : H20 - Maladies des plantes

Auteurs et affiliations

• Rang Cécile, CIRAD-AMIS-BIOTROP (FRA)
• Vachon Vincent
• De Maagd R.
• Villalon M.
• Schwartz Jean Louis
• Bosch D.
• Laprade Raynald

Source : Cirad - Agritrop (https://agritrop.cirad.fr/392095/)

Métriques

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