Question

What is true about Bt toxin?

• A. The concerned Bacillus has antitoxins
• B. The inactive protoxin gets converted into active form in the insect gut
• C. Bt protein exists as active toxin in the bacillus
• D. The activated toxin enters the ovaries of the pest to sterilise it and thus prevent its multiplication

Answer 1

The correct option is B The inactive protoxin gets converted into active form in the insect gut

Bacillus thuringiensis (or Bt) is a Gram-positive, soil-dwelling bacterium, that during sporulation produce crystal proteins called Bt toxin. The Bt toxin on being ingested by an insect dissolve in the high pH of the insect gut and become active. The active toxin attacks the gut cells of the insect, punching holes in the lining and thus killing the host.
Therefore, of the given statements, the correct option is "The inactive protoxin gets converted into an active form in the insect gut".