The A and B polypeptides chains in insulin are linked together by which bond?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Disulphide
Option (2) Disulphide — Correct. In human insulin, chains A and B are linked together by disulphide bridges (S-S bonds). Eli Lilly made the two chains separately and joined them by forming these bonds.
NCERT Extract:
Genetically Engineered Insulin – “… Insulin used for diabetes was earlier extracted from pancreas of slaughtered cattle and pigs. Insulin from an animal source, though caused some patients to develop allergy or other types of reactions to the foreign protein. Insulin consists of two short polypeptide chains: chain A and chain B, that are linked together by disulphide bridges (Figure 10.3).”
Figure 10.3 Maturation of pro-insulin into insulin (simplified)