All the following are the properties of the enzyme taq polymerase except:

Options

A. It is thermostable DNA polymerase
B. It is isolated from a bacterium, Thermus aquaticus
C. It is used for amplification of gene of interest using PCR
D. It is thermostable RNA polymerase

Answer

To solve the question regarding the properties of the enzyme Taq polymerase, we will analyze the properties mentioned and identify which one does not belong.

### Step-by-Step Solution:

1. **Understanding Taq Polymerase**: Taq polymerase is an enzyme that is primarily used in the Polymerase Chain Reaction (PCR) to amplify DNA. It is derived from the bacterium Thermus aquaticus, which is known for its ability to withstand high temperatures.

2. **Identifying Properties of Taq Polymerase**:
- **Thermostability**: Taq polymerase is thermostable, meaning it can function at high temperatures (up to about 95 degrees Celsius). This property is crucial for PCR, as the process involves repeated heating and cooling cycles.
- **Source**: It is isolated from the bacterium Thermus aquaticus, which thrives in hot environments, contributing to the enzyme's heat resistance.
- **Function**: Taq polymerase is used in the amplification of DNA, making it essential for PCR processes.

3. **Evaluating the Options**:
- **Option 1**: Thermostable DNA polymerase - This is true.
- **Option 2**: Isolated from Thermus aquaticus - This is also true.
- **Option 3**: Used in the amplification of genes of interest using PCR - This is true.
- **Option 4**: It is a thermostable RNA polymerase - This is false because Taq polymerase is a DNA polymerase, not an RNA polymerase.

4. **Conclusion**: The property that does not apply to Taq polymerase is that it is a "thermostable RNA polymerase." Therefore, the correct answer is option 4.

### Final Answer:
The property of Taq polymerase that is incorrect is: **It is a thermostable RNA polymerase.**

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