First hormone produced artificially by culturing bacteria is

Options

A. Insulin
B. Thyroxine
C. Testosterone
D. Adrenaline

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the first hormone produced artificially by culturing bacteria.

2. **Recall the Hormone**: The first hormone that was produced artificially using bacterial culture is insulin.

3. **Understand Insulin Production**: Insulin is naturally produced in the pancreas, specifically by the beta cells of the islets of Langerhans.

4. **Function of Insulin**: Insulin plays a crucial role in regulating blood glucose levels. When blood glucose levels rise, insulin helps convert glucose into glycogen for storage in the liver.

5. **Historical Context**: Before the artificial production of insulin, it was extracted from the pancreases of slaughtered animals, such as cattle and pigs. This method had drawbacks, including potential allergic reactions in humans due to the foreign proteins.

6. **Artificial Production Process**: In 1983, the American company Eli Lilly successfully produced human insulin by introducing the DNA sequences for the A and B chains of insulin into the plasmid of E. coli bacteria.

7. **Chain Production**: The E. coli bacteria then produced the two chains of insulin separately. These chains were then extracted and combined through disulfide bonds to form the active form of human insulin.

8. **Conclusion**: Therefore, the answer to the question is that the first hormone produced artificially by culturing bacteria is insulin.

**Final Answer**: Insulin

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