Which step proved to be the main challenging obstacle in the production of human insulin by genetic engineering?

Options

A. Removal of C-peptide from active insulin.
B. Getting insulin assembled into a mature from.
C. Addition of C-peptide tro pro-insulin.
D. Splitting A and B polypeptide chains.

Answer

**Step-by-Step Solution:**

1. **Understanding Human Insulin Production**: Human insulin, also known as Humulin, is produced through genetic engineering to help diabetic patients who cannot produce insulin naturally. The goal is to create a large quantity of insulin for lifelong treatment.

2. **Genetic Engineering Process**: The process involves taking a DNA sequence that codes for insulin and inserting it into bacteria. These bacteria then read the DNA as their own and start producing insulin.

3. **Structure of Insulin**: Human insulin consists of two chains, known as the A chain and the B chain. However, the precursor to insulin, known as proinsulin, contains an additional C-peptide chain, making it an immature form of insulin.

4. **Challenge in Insulin Production**: The main challenge in producing functional human insulin is to remove the C-peptide from the proinsulin to create the mature insulin form that consists only of the A and B chains.

5. **Conclusion**: The step that proved to be the main challenging obstacle in the production of human insulin by genetic engineering is "getting insulin assembled into a mature form," specifically the removal of the C-peptide chain.

**Final Answer**: The main challenging obstacle in the production of human insulin by genetic engineering is getting insulin assembled into a mature form (removal of C-peptide).

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