Question

The insulin synthesised in our body is different from that synthesised by Eli Lilly company using recombinant DNA technology. Differentiate between them.

Answer 1

Feature	Human Insulin	Recombinant Insulin (e.g., Eli Lilly)
Synthesis process:	Produced as proinsulin, which has an additional peptide chain (the C peptide) that is eliminated during maturation.	Produced as mature insulin without the use of the C peptide.
Structure:	It is made from proinsulin, which contains C-peptide, and has A and B chains connected by disulphide bonds.	lacks the C peptide but is made up of A and B chains connected by disulphide bridges.
Production:	Produced by beta cells in the islets of Langerhans of the pancreas.	Produced by recombinant DNA techniques in yeast or bacteria.
Processing:	To eliminate the C peptide and create mature insulin, post-translational modification is necessary.	Since it is directly synthesized in its mature state, post-translational modification is not necessary.