DNA polymerase is isolated from bacteria

Options

A. E. coli
B. Bacillus thuringiensis
C. Thermus aquaticus
D. Agrobacterium

Answer

To solve the question regarding the isolation of DNA polymerase from bacteria, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which bacterium DNA polymerase is isolated from, specifically in the context of its use in PCR (Polymerase Chain Reaction).

2. **Identify the Options**: The options provided are:
- E. coli
- Bacillus thuringiensis
- Thermus aquaticus
- Agrobacterium

3. **Recall Key Information**:
- DNA polymerase is an enzyme crucial for DNA replication and is particularly important in the PCR process.
- Taq polymerase is a specific type of DNA polymerase that is heat-stable, allowing it to function at high temperatures during PCR.

4. **Connect Taq Polymerase to its Source**:
- Taq polymerase is derived from the bacterium **Thermus aquaticus**, which is known for its ability to thrive in high-temperature environments (thermophilic).

5. **Evaluate the Options**:
- **E. coli**: Commonly used in molecular biology but not the source of Taq polymerase.
- **Bacillus thuringiensis**: Known for its insecticidal properties, not for Taq polymerase.
- **Thermus aquaticus**: Correct answer, as it is the source of Taq polymerase.
- **Agrobacterium**: Known for its role in plant genetics, not for Taq polymerase.

6. **Conclusion**: The correct answer is **Thermus aquaticus**, as it is the bacterium from which Taq polymerase is isolated.

### Final Answer:
The DNA polymerase is isolated from **Thermus aquaticus**.

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