Question

How is the insulin produced by the human body different from the insulin produced by the above-mentioned company?

Answer 1

Insulin consists of two short polypeptide chains: chain A and chain B, that are linked together by disulphide bridges. In mammals, including humans, insulin is synthesised as a pro-hormone (like a pro-enzyme, the pro-hormone also needs to be processed before it becomes a fully mature and functional hormone) which contains an extra stretch called the C peptide. This C peptide is not present in the mature insulin.

Insulin produced by Eli Lily company didn't have this C peptide, they produced A and B chains separately. Later, disulphide bonds were created between these chains.