A microbe employed in bioremediation i.e., conversion of heavy metal pollutants of soil inot less toxic salts is :

Options

A. Rhizobium
B. E.coli
C. Trichoderma
D. Pseudomonas

Answer

To solve the question about which microbe is employed in bioremediation for converting heavy metal pollutants in soil into less toxic salts, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Bioremediation**:
- Bioremediation is a technique that uses microbes or bacteria to remove contaminants and toxins from the environment, including soil and water.

2. **Evaluate the Options**:
- The options given are:
- **Rhizobium**: A nitrogen-fixing bacterium that helps in enriching soil but is not primarily used for bioremediation of heavy metals.
- **E. coli**: A bacterium that has some applications in bioremediation, but it is not specifically known for heavy metal detoxification.
- **Trichoderma**: A fungus used mainly for controlling plant diseases and not specifically for heavy metal bioremediation.
- **Pseudomonas**: A genus of bacteria known for its ability to degrade various pollutants, including heavy metals and polycyclic aromatic hydrocarbons.

3. **Identify the Correct Microbe**:
- Among the options, **Pseudomonas** is recognized for its capability to degrade toxic compounds and is widely used in bioremediation processes, particularly for heavy metal pollution.

4. **Conclusion**:
- Therefore, the correct answer to the question is **Pseudomonas** as it is specifically employed in bioremediation to convert heavy metal pollutants into less toxic forms.

### Final Answer:
The microbe employed in bioremediation for the conversion of heavy metal pollutants in soil into less toxic salts is **Pseudomonas**.

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