Bt-toxins are released as inactive crystals in the bacterial body. What happens to it in the cotton boll worm body that it kills the boll worm?

• Through genetic engineering it is possible to develop crops that are resistant to insects. One of the insect resistant plants that are produced is Bt cotton which is resistant to insect Bacillus thuringiensis.

• Bacillus thuringensis produce the Bt toxins. Bt toxins are produced as inactive crystals in the bacterial body.

• Since they are present in an inactive form inside the bacterial body, the bacteria themselves aren’t killed.

• It gets converted into an active protein in the cotton ball worm.

• The activation happens because of the alkaline pH of the gut of the boll worm.

• The toxin binds to the midgut cells and cause lysis creating pores.

• This causes the cell to swell up and eventually kill the worm.