Enzyme 'Taq polymerase' used in PCR, has been isolated from bacterium

Options

A. Agrobacterium tumefaciens
B. Thermus aquaticus
C. Streptomyces albus
D. Escherichia coil

Explanation

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks about the source of the enzyme 'Taq polymerase' used in PCR (Polymerase Chain Reaction).

2. **Identify the Options**: The options provided are:
- A. Agrobacterium tumefaciens
- B. Thermus aquaticus
- C. Streptomyces albus
- D. Escherichia coli

3. **Know the Source of Taq Polymerase**: Taq polymerase is a heat-stable DNA polymerase enzyme that is crucial for PCR. It is known to be isolated from a specific bacterium that thrives in high-temperature environments.

4. **Analyze the Options**:
- **Agrobacterium tumefaciens**: This bacterium is known for its role in plant genetic engineering but is not the source of Taq polymerase.
- **Thermus aquaticus**: This is a thermophilic bacterium from which Taq polymerase is isolated. It is adapted to high temperatures, making it ideal for PCR.
- **Streptomyces albus**: This bacterium is known for producing antibiotics, not Taq polymerase.
- **Escherichia coli**: While this bacterium is widely used in biotechnology, it does not produce Taq polymerase.

5. **Select the Correct Answer**: Based on the information, the correct answer is **B. Thermus aquaticus**.

6. **Conclusion**: Taq polymerase is isolated from the bacterium Thermus aquaticus, making option B the correct choice.

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