Which of the following group of enzymes helps in catalysing a transfer of a group (other than hydrogen) between a pair of substrates ?

Options

A. Oxidoreductases
B. Transferases
C. Lyases
D. Isomerases

Answer

To solve the question regarding which group of enzymes catalyzes the transfer of a group (other than hydrogen) between a pair of substrates, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which group of enzymes facilitates the transfer of a functional group (like methyl, glycosyl, or phosphoryl) from one substrate to another, excluding hydrogen.

2. **Review the Options**: The options provided are:
- A) Oxidoreductase
- B) Transferase
- C) Lyase
- D) Isomerase

3. **Analyze Each Option**:
- **Oxidoreductase**: This group of enzymes is involved in oxidation-reduction reactions, where electrons (and often hydrogen) are transferred between substrates. Thus, it does not fit our requirement of transferring a group other than hydrogen.
- **Transferase**: This group of enzymes is specifically responsible for transferring functional groups (like methyl, glycosyl, or phosphoryl) from one substrate to another. This matches the requirement of the question.
- **Lyase**: Lyases catalyze the addition or removal of groups to form double bonds or to break them, but they do not specifically transfer groups between substrates.
- **Isomerase**: Isomerases convert one isomer into another, which involves rearranging atoms within a single molecule rather than transferring groups between different substrates.

4. **Conclusion**: Based on the analysis, the correct answer is **Transferase**, as it is the only group of enzymes that catalyzes the transfer of a group (other than hydrogen) between a pair of substrates.

### Final Answer:
**B) Transferase**

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