"Haem" is prosthetic group for which of the following enzyme or enzymes

Options

A. Catalase
B. Peroxidase
C. Oxidase
D. 1 & 2

Answer

To determine which enzymes have "haem" as a prosthetic group, we need to analyze the options given in the question: catalyst, peroxidase, oxidase, and the combination of the first two.

### Step-by-Step Solution:

1. **Understanding Prosthetic Groups**:
- Prosthetic groups are non-amino acid components that are tightly and permanently attached to the enzyme. They are essential for the enzyme's activity.
- When a protein is combined with a prosthetic group, it is referred to as a "holoenzyme," while the protein without it is called an "apoprotein."

2. **Identifying the Structure of Haem**:
- The "haem" group is a type of prosthetic group that contains an iron atom (Fe²⁺) and is derived from a larger structure known as porphyrin, which consists of four pyrrole rings.

3. **Listing Enzymes Associated with Haem**:
- Common enzymes that utilize the haem group include:
- **Catalase**: An enzyme that catalyzes the decomposition of hydrogen peroxide into water and oxygen.
- **Peroxidase**: An enzyme that catalyzes the reduction of peroxides.
- **Cytochrome**: Involved in electron transport and redox reactions.
- **Hemoglobin**: A protein in red blood cells that carries oxygen.
- **Myoglobin**: A protein that carries oxygen in muscle cells.

4. **Analyzing the Options**:
- **Catalase**: Yes, it contains haem as a prosthetic group.
- **Peroxidase**: Yes, it also contains haem as a prosthetic group.
- **Oxidase**: Generally does not contain haem; instead, it may use other cofactors.

5. **Conclusion**:
- Since both catalase and peroxidase contain the haem prosthetic group, the correct answer is **1 and 2**.

### Final Answer:
The correct answer is **1 and 2 (Catalase and Peroxidase)**.