Select the option which completes the given equation for reductive amination
`overset((I))to+NH_(4)^(+)+NAD(P)Hoverset((II))to"Glutamate"+H_(2)O+NAD(P)`

Options

A. (a) `{:("(I)","(II)"),(alpha-"ketoglutaric acid","Transaminase"):}`
B. (b) `{:("(I)","(II)"),(alpha-"ketoglutaric acid","Glutamate dehydrogenase"):}`
C. (c) `{:("(I)","(II)"),(alpha-"Asparagine","Glutamate dehydrogenase"):}`
D. (d) `{:("(I)","(II)"),(alpha-"Glutamine","Transaminase"):}`

Answer

To complete the equation for reductive amination, we need to identify the correct components that participate in the reaction. The equation provided is:

`overset((I))to + NH_(4)^(+) + NAD(P)H overset((II))to "Glutamate" + H_(2)O + NAD(P)`

### Step-by-Step Solution:

1. **Identify the Keto Acid**: The first component (I) in the reaction is a keto acid. In the context of reductive amination, the most relevant keto acid is **alpha-ketoglutaric acid** (also known as alpha-ketoglutarate). This compound is an important intermediate in the Krebs cycle.

2. **Combine with Ammonia**: In the reductive amination process, ammonia (NH₄⁺) combines with alpha-ketoglutaric acid. This reaction is facilitated by the enzyme glutamate dehydrogenase.

3. **Enzymatic Reduction**: The enzyme responsible for this reaction is **glutamate dehydrogenase**. This enzyme catalyzes the conversion of alpha-ketoglutaric acid and ammonia into glutamate.

4. **Final Products**: The products of this reaction are glutamate, water (H₂O), and NAD(P) (which is reduced to NAD(P)H in the process).

5. **Complete the Equation**: Thus, the complete equation can be written as:
- `alpha-ketoglutaric acid + NH₄⁺ + NAD(P)H → Glutamate + H₂O + NAD(P)`

6. **Select the Correct Options**: Therefore, the correct option that completes the equation is:
- (I) **alpha-ketoglutaric acid**
- (II) **glutamate dehydrogenase**

### Final Answer:
The correct answer is option B: **alpha-ketoglutaric acid** and **glutamate dehydrogenase**.

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