Question

Illustrate using any one example of transgenic bacteria.

Answer 1

Human insulin has been prepared by genetic technology. Insulin is made up of two small polypeptide chains, chain 'A' and chain 'B' which are linked to each other by disulphide bonds. In human insulin, a pro-hormone is synthesised which contains C peptide. This peptide 'C' is not found in mature insulin, it gets separated from insulin at the time of maturation. In 1983, two DNA sequences corresponding to chain 'A' and 'B' of human insulin were prepared, which were inserted into the plasmid of E. coli to produce insulin chains. These separately produced chains 'A' and 'B' were taken out and joined to each other by disulphide bonds to prepare human insulin. Insulin is a useful medicine for controlling diabetes. The credit for cloning the insulin gene goes to Dr. Saran Narang of Indian origin. He conducted his experiment in Ottawa, Canada.