For its activity, carboxypeptidase requires

Options

A. Niacin
B. Copper
C. Zinc
D. Iron

Answer

**Step-by-Step Solution:**

1. **Understanding Carboxypeptidase**: Carboxypeptidase is an enzyme that plays a crucial role in the digestion of proteins. It breaks down peptides into amino acids by cleaving off the terminal amino acid from the carboxyl end of the peptide chain.

2. **Identifying the Requirement**: Enzymes often require specific cofactors to function effectively. These cofactors can be metal ions or organic molecules that assist in the enzyme's catalytic activity.

3. **Analyzing the Options**: The options provided are niacin, copper, zinc, and iron. We need to determine which of these is essential for the activity of carboxypeptidase.

4. **Researching Metal Cofactors**: It is known that certain enzymes, including carboxypeptidase, require metal ions as cofactors. Common metal cofactors include zinc, magnesium, and manganese.

5. **Determining the Correct Cofactor**: Among the options listed, zinc is specifically known to be a necessary cofactor for carboxypeptidase. It helps in the enzyme's activity by forming a coordination complex with the substrate, facilitating the reaction.

6. **Conclusion**: Therefore, for its activity, carboxypeptidase requires zinc.

**Final Answer**: Carboxypeptidase requires zinc for its activity.

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