Two bacteria most useful in genetic engineering are

Options

A. Rhizobium and Azotobacter
B. Escherichia and Agrobacterium
C. Rhizobium and Diplococcus
D. Nitrosomonas and Klebsiella

Answer

**Step-by-Step Solution:**

1. **Identify Key Bacteria in Genetic Engineering**: The question asks for two bacteria that are most useful in genetic engineering.

2. **First Bacterium - Agrobacterium tumefaciens**:
- Agrobacterium tumefaciens is a soil bacterium known for its role in the genetic engineering of plants.
- It contains a plasmid (Ti plasmid) that can transfer genes into plant cells, making it a vital tool for creating genetically modified plants.

3. **Second Bacterium - Escherichia coli (E. coli)**:
- E. coli is one of the most extensively studied bacteria in the field of genetics and biotechnology.
- It is widely used for cloning and expressing genes, including the production of human insulin (Humulin) and other important proteins.
- E. coli is favored in genetic engineering due to its ability to grow rapidly and produce large quantities of the desired product from introduced genes.

4. **Conclusion**: The two bacteria that are most useful in genetic engineering are:
- **Agrobacterium tumefaciens**
- **Escherichia coli (E. coli)**

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