Question

How did an American Company, Eli Lilly use the knowledge of rDNA technology to produce insulin?

Answer 1

Hint: Insulin is made up of two polypeptide chains. These are joined by sulphur bonds using genetic engineering or recombinant DNA technology.

Complete answer: Human insulin, produced in E. coli for clinical use is known as Humulin. Immature pro-insulin in humans comprises chains of A and B-peptides. There is a short polypeptide chain which connects the A and B chains of insulin. It is known as the C peptide. In mature insulin, it is not present. During maturation, C peptide gets removed. In the plasmids of E.coli bacteria, the gene responsible for the development of human insulin was incorporated using rDNA technology principles. As bacteria grows, greater amounts of the gene product could be obtained in the laboratory. Here, two DNA sequences - A and B human insulin chains were first prepared by the American company Eli Lilly in 1983. The major challenge was to assemble these two into a mature form in order to manufacture the insulin. But it was solved in the following way: Two chains obtained separately were tied together with the help of sulphur bonds. More specifically, the two chains (A and B) were produced and extracted and then combined with disulphide bonds to form the humulin. The biosynthetic human insulin has greater purity in contrast to animal insulin, thereby reducing the immune response.

Note: Biotechnology is commonly used in various fields to produce useful products for human benefits, such as medicine, agriculture, food processing, etc. In the field of medicine, biotechnology has a number of uses such as the production of recombinant insulin or human insulin, gene therapy, development of vaccines (oral or edible), in the field of pharmacogenomics, for the purpose of molecular diagnosis etc.