Enzymes that utilize ATP in phosphate transfer require an alkaline earth metal (M) as the cofactor M is

Options

A. Sr
B. Be
C. Mg
D. Ca

Explanation

To solve the question about which alkaline earth metal (M) is required as a cofactor for enzymes that utilize ATP in phosphate transfer, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Role of Cofactors**:
- Enzymes often require additional components called cofactors to function properly. These can be metal ions, organic molecules, or vitamins.

2. **Identifying the Type of Enzymes**:
- The question specifies enzymes that utilize ATP in phosphate transfer. These enzymes are typically kinases, which are involved in phosphorylation reactions.

3. **Recognizing the Importance of Magnesium**:
- Among the alkaline earth metals, magnesium (Mg) is known to play a crucial role in many enzymatic reactions, particularly those involving ATP.

4. **Examining Other Options**:
- The other alkaline earth metals listed (Beryllium, Calcium, and Strontium) do not have the same established role in ATP-dependent phosphorylation reactions as magnesium does.

5. **Conclusion**:
- Therefore, the alkaline earth metal (M) that acts as a cofactor for enzymes utilizing ATP in phosphate transfer is **Magnesium (Mg)**.

### Final Answer:
The alkaline earth metal (M) that acts as a cofactor for enzymes utilizing ATP in phosphate transfer is **Magnesium (Mg)**.

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