Which of the following is a cofactor for the proteolytic enzyme carboxpeptidase?

Options

A. Zinc
B. Copper
C. Calcium
D. Magnesium

Answer

To determine the cofactor for the proteolytic enzyme carboxypeptidase, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of Carboxypeptidase**:
- Carboxypeptidase is a proteolytic enzyme that plays a crucial role in protein metabolism by hydrolyzing peptide bonds at the carboxyl-terminal end of proteins.

2. **Identify Potential Cofactors**:
- The options provided are zinc, copper, calcium, and magnesium. We need to identify which of these elements acts as a cofactor for carboxypeptidase.

3. **Research Known Cofactors**:
- Cofactors are non-protein chemical compounds that are required for the biological activity of certain enzymes. They can be metal ions or organic molecules.

4. **Determine the Cofactor for Carboxypeptidase**:
- Carboxypeptidase specifically requires zinc as a cofactor. The zinc ion is essential for the enzyme's catalytic activity, aiding in the hydrolysis of the carboxyl group in amino acids.

5. **Conclude the Answer**:
- Since zinc is identified as the necessary cofactor for carboxypeptidase, the correct answer to the question is **Zinc**.

### Final Answer:
The cofactor for the proteolytic enzyme carboxypeptidase is **Zinc**.

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