The prosthetic group attached to the enzymes of vitamin `B_(12)` at the time of reaction is

Options

A. cellulose
B. 5 - deoxy adenosyl
C. `beta`-methyl aspartic acid
D. glutamic acid

Answer

To answer the question regarding the prosthetic group attached to the enzymes of vitamin B12 during a reaction, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the prosthetic group associated with the enzyme of vitamin B12 during a reaction. A prosthetic group is a non-polypeptide unit that is tightly and permanently attached to a protein and is essential for the biological activity of that protein.

2. **Identifying Vitamin B12**: Vitamin B12 is also known as cobalamin. It is a complex molecule that plays a crucial role in various biological processes, including DNA synthesis and red blood cell formation.

3. **Recognizing the Enzyme**: The enzyme associated with vitamin B12 is often referred to as a cobalamin-dependent enzyme. One of the well-known enzymes that utilize vitamin B12 is methylmalonyl-CoA mutase.

4. **Defining the Prosthetic Group**: The prosthetic group is a non-amino acid component that is part of the structure of certain proteins, specifically conjugated proteins or heteroproteins.

5. **Identifying the Specific Prosthetic Group**: For vitamin B12, the specific prosthetic group that is attached to the enzyme is known as **5'-deoxyadenosylcobalamin** (also referred to as adenosylcobalamin). This form of vitamin B12 acts as a cofactor for the enzyme.

6. **Conclusion**: Therefore, the correct answer to the question is that the prosthetic group attached to the enzymes of vitamin B12 at the time of reaction is **5'-deoxyadenosylcobalamin**.

### Final Answer:
The prosthetic group attached to the enzymes of vitamin B12 at the time of reaction is **5'-deoxyadenosylcobalamin**.

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