NEET2011ZoologyBiotechnology and Its ApplicationsActual
Bacillus thuringiensis forms protein crystals, which contain insecticidal protein
Options
- Abinds with epithelial cells of midgut of the insect pest ultimately killing it
- Bis coded by several genes including the gene cry
- Cis activated by acid of pH of the foregut of the insect pest
- Ddoes not kill the carrier bacterium which is itself resistant to this toxin
Correct answer
A. binds with epithelial cells of midgut of the insect pest ultimately killing it
Step-by-step solution
Soil bacterium Bacillus thuringiensis (Bt) possesses is a gene family cry gene (1-40) over its plasmid, which forms an 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 inactive protoxins but once an insect ingests the inactive toxin, it is converted into an active form of toxin due to the alkaline pH of the gut which solubilise the c