Enzyme enolase catalyses the conversion of 2-PGA to phosphoenol pyruvic acid in the presence of cofactor

Options

A. `Mn^(2+)`
B. `Fe^(2+)`
C. `Mg^(2+)`
D. `Zn^(2+)`

Answer

To solve the question regarding the enzyme enolase and its role in the conversion of 2-phosphoglycerate (2-PGA) to phosphoenolpyruvic acid (PEP), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Enzyme and Reaction**:
- The enzyme in question is enolase, which is also known as phosphopyruvate hydratase. It catalyzes the conversion of 2-phosphoglycerate (2-PGA) to phosphoenolpyruvic acid (PEP).

2. **Understanding the Reaction Context**:
- This reaction is part of the glycolytic pathway, specifically the 8th step of glycolysis. Glycolysis is the metabolic pathway that converts glucose into pyruvate, generating ATP and NADH in the process.

3. **Identify the Cofactor Required**:
- Enzymes often require cofactors to assist in catalyzing reactions. The question lists potential cofactors: Mn²⁺, Fe²⁺, Mg²⁺, and Zn²⁺.

4. **Determine the Correct Cofactor for Enolase**:
- Enolase specifically requires magnesium ions (Mg²⁺) as a cofactor for its enzymatic activity. Magnesium is a common activator for many enzymes involved in metabolic processes.

5. **Conclusion**:
- Therefore, the correct answer to the question is that enolase catalyzes the conversion of 2-PGA to phosphoenolpyruvic acid in the presence of the cofactor Mg²⁺.

### Final Answer:
The cofactor required for the enzyme enolase in the conversion of 2-PGA to phosphoenolpyruvic acid is Mg²⁺.

---