Question

6) The translated peptide for human (pre)insulin is modified following translation. Modification includes cleavage into 3 peptides called A, B, and C by proteases. Only the A and B peptides are present in the active form of insulin and they are attached to each other via disulfide bonds. Examine a structure for human insulin (IZNI in the protein data base) and answer the following: a) How many disulfide bonds does human insulin have? b) Describe the secondary structure of insulin.

Answer 1

6 ans)- Insulin protein decreases the blood sugar level. Primaeily It have three polypeptides- bie. Pre-insulin. Modification includes clevage q c chain So, Activated form o insulio consist oq Å F B chain. ay Two disulphide bond are present bet ASB polypeptide in IZNI Structure. One is present 34-3.of second is present in 94-94 amino acid, by secondary structure q insulin is right handed alpha belle. Although the amino acid sequence of insulin Varies among Species , but coekin segment is highly conserved. These similarities in the amino acid Sequence o inswin lead to three dimensional structure. Intermoleculae hydrogen bonding in the alpha-helia is beth the amide groups.