Bacillus thuringiensis forms protein crystals, which contain insecticidal protein
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binds with epithelial cells of midgut of the insect pest ultimately killing it
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is coded by several genes including the gene cry
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is acitvated by acid of pH of the foregut is the insect pest
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does not kill the carrier bacterium which is itself resistant to this toxin
A.
binds with epithelial cells of midgut of the insect pest ultimately killing it
Soil bacterium Bacillus thuringuensis (Bt) possesses is a gene family cry gene (1-40) over its plasmid, which forms endotoxic proteins, cry protein (protein crystals) during a particular phase of its growth. These crystals contain a toxic insecticidal protein.This toxin, however, does not kill the Bacillus.Actually, the BT toxin protein exists as an inactive toxin, it is converted into an active form of toxin due to the alkaline pH of the gut which solubilizes the crystals. The activated toxin binds to the surface of midgut epithelial and lysis, and eventually cause the death of the insect.
