Question

The most extensively used bacteria in genetic engineering is

• A. Escherichia
• B. Salmonella
• C. Clostridium
• D. Bacillus

Answer 1

The correct option is A Escherichia

Techniques to alter the chemistry of genetic material (DNA and RNA), to introduce these into host organisms and thus change the phenotype of the host organism is called genetic engineering.

Bacillus thuringiensis is a bacterium containing cry gene which codes for an insecticidal protein. This gene is used in genetic engineering to create pest resistant plants like Bt cotton, Bt brinjal etc.

Clostridium is a bacterium used in genetic engineering for producing various products. For example, Clostridium botulinum is used for the production of botox (botulinum toxin) which is used in cosmetic surgery to reduce the signs of aging.

Escherichia coli is the widely used bacterium in genetic engineering due to the following reasons:

• It has a generation time of 20 minutes.
• Easy to culture.
• Easy to transform.
• Used as a host for cloning of recombinant DNA.
• Used for expressing and isolating recombinant products.

First recombinant DNA was formed by inserting an antibiotic-resistant gene into the naive plasmid of Salmonella typhimurium.

Plasmids are circular extrachromosomal DNA that can replicate inside the organism. Salmonella is genetically engineered to deliver therapeutic proteins and attenuated vaccines.

Hence the correct option is
c. Escherichia