Choose correct about Genetically Engineered Insulin.

All of these.

a-Insulin used for diabetes was earlier extracted from pancreas of slaughtered cattle and pigs.

b-Insulin consists of two short polypeptide chains: chain A and chain B, that are linked together by disulphide bridges.

c-Eli Lilly an American company prepared two DNA sequences corresponding to A and B, chains of human insulin.

d-All of these is the correct option .

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 . Eli Lilly an American company prepared two DNA sequences corresponding to A and B, chains of human insulin and introduced them in plasmids of E. coli to produce insulin chains. Chains A and B were produced separately, extracted and combined by creating disulfide bonds to form human insulin.