Question

Question: In determining the primary structure of insulin, what would lead you to conclude that insulin had more than one polypeptide chain?

Short answer

The answer is:

The treatment of insulin with Edman’s reagent would give two PTH amino acids.

Step-by-step solution

Step-by-Step Solution Step 1: Insulin

Human pancreas secretes insulin which controls the blood sugar level. It is composed of a chain of amino acids called peptides and has a single polypeptide chain.

Explanation

Insulin comprises of two peptide chains. On treatment with the Edman’s reagent (heptfluorobutyric acid) would release two PTH amino acids in approximately equal amounts.

Hence on the determination of the primary structure of insulin, it can be concluded that there will be more than one polypeptide in it.