Which bacterium has been genetically modified for producing human insulin ?

Options

A. Lactobacillus
B. Bacillus vulgaris
C. Pseudomones putida
D. E.coli

Answer

To answer the question "Which bacterium has been genetically modified for producing human insulin?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify the bacterium that has been genetically modified to produce human insulin.

2. **Identifying Options**: The options provided are:
- Lactobacillus
- Bacillus vulgaris
- Pseudomonas putida
- Escherichia coli (E. coli)

3. **Knowledge of Genetic Modification**: Human insulin can be produced using genetically modified organisms. This involves inserting the human insulin gene into a bacterium.

4. **The Process of Genetic Modification**:
- The gene responsible for producing human insulin is extracted from human DNA using restriction enzymes.
- This gene is then inserted into a plasmid (a small circular DNA molecule) using ligase enzymes.
- The plasmid is introduced into bacterial cells, allowing them to replicate and produce human insulin.

5. **Identifying the Correct Bacterium**: Among the options, Escherichia coli (E. coli) is the bacterium that has been predominantly used for this purpose. It is well-studied and has been successfully modified to produce recombinant human insulin for therapeutic use.

6. **Conclusion**: Therefore, the correct answer to the question is **Escherichia coli (E. coli)**.

### Final Answer:
The bacterium that has been genetically modified for producing human insulin is **Escherichia coli (E. coli)**.

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