In a reaction, 120 substrate molecules are converted to products in 5 minutes . TON of enzyme is 12. What is the number of enzymes catalysing the reaction ?

Options

A. 10
B. 2
C. 12
D. 8

Answer

To solve the problem, we need to determine the number of enzymes catalyzing the reaction given the following information:

- 120 substrate molecules are converted to products in 5 minutes.
- The turnover number (TON) of the enzyme is 12.

### Step-by-Step Solution:

1. **Calculate Vmax (Maximum Rate of Reaction)**:
- Vmax can be calculated using the formula:
\[ Vmax = \frac{\text{Total Substrate Converted}}{\text{Time}} \]
- Here, the total substrate converted is 120 molecules, and the time is 5 minutes.
- Therefore:
\[ Vmax = \frac{120 \text{ molecules}}{5 \text{ minutes}} = 24 \text{ molecules/minute} \]

2. **Use the TON to Find the Number of Enzymes**:
- The turnover number (TON) is defined as the number of substrate molecules converted to product by one enzyme in one minute.
- Given that the TON is 12, we can find the number of enzymes (ET) using the formula:
\[ \text{Number of Enzymes} (ET) = \frac{Vmax}{TON} \]
- Substituting the values we have:
\[ ET = \frac{24 \text{ molecules/minute}}{12} = 2 \]

3. **Conclusion**:
- The number of enzymes catalyzing the reaction is 2.

### Final Answer:
The number of enzymes catalyzing the reaction is **2**.

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