Nitrite reductase enzyme is used to convert

Options

A. Nitrate into nitrite ion
B. Nitrogen of atmosphere into ammonia
C. Ammonia into nitrates
D. Nitrite to ammonium ion

Answer

**Step-by-Step Solution:**

1. **Understanding the Function of Nitrite Reductase:**
- Nitrite reductase is an enzyme that catalyzes the reduction of nitrite (NO2-) to ammonium ions (NH4+).

2. **Evaluating the Options:**
- **Option 1:** Nitrate into nitrite - This reaction is catalyzed by nitrate reductase, not nitrite reductase. Therefore, this option is incorrect.
- **Option 2:** Atmospheric nitrogen into ammonia - This conversion is facilitated by the enzyme nitrogenase, not nitrite reductase. Thus, this option is also incorrect.
- **Option 3:** Ammonia into nitrates - This process is carried out by ammonia oxidizers, making this option incorrect as well.
- **Option 4:** Nitrite to ammonium ions - This is the correct function of nitrite reductase, as it catalyzes the reduction of nitrite to ammonium ions.

3. **Conclusion:**
- Based on the evaluation of all options, the correct answer is that nitrite reductase enzyme is used to convert nitrite to ammonium ions.

**Final Answer:**
Nitrite reductase enzyme is used to convert nitrite to ammonium ions.

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