Question

What is the full form of BT?

Answer 1

BT:

1. The full form of BT is Bacillus thuringiensis.
2. BT crops are transgenic crops that are genetically engineered from the DNA of bacterium Bacillus thuringiensis.
3. Bacillus thuringiensis in the plant cell, thereby, protecting the crops from pests.
4. The bacterium secretes specific proteins known as “cry proteins” that are toxic to insects.
5. A few of the BT crops include cotton, brinjal, corn, etc.

CRY gene:

1. The cry family of genes generated during the late exponential growth of Bacillus thuringiensis is a large and still growing family of homologous genes, each gene strongly specific to only one or a few insect species. It encodes a protein with active activity.
2. The Bacillus thuringiensis 'cry gene' encodes a toxic insecticidal protein that exists as an inactive protoxin.
3. When these proteins are genetically engineered into cotton crops, they confer pest resistance to the bollworm and prevent damage.

CRY protein:

1. The cry protein is an insect venom crystal protein expressed by the cry gene. Bacillus thuringiensis bacteria produce it in an inactive state.
2. The alkaline pH of insects helps activate cry proteins when they are consumed by insects.
3. These substances are not toxic to humans or other animals, but they do affect insects.

Organisms that produce cry proteins:

1. Bacillus thuringiensis bacteria synthesize this protein. With the exception of some insects, this bacterium is considered non-toxic to plants and animals.
2. It is highly selective, killing only certain insects. Most beneficial insects such as ladybugs and parasitic wasps are unaffected.
3. Humans utilize cry proteins to produce insect-resistant crops such as Bt cotton and Bt eggplant.