`alpha`-Ketoglutarate dehydrogenase brings about

Options

A. Oxidation and decarboxylation
B. Oxidation
C. Decarboxylation
D. Reduction.

Answer

**Step-by-Step Solution:**

1. **Identify the Enzyme and its Function**: The enzyme in question is alpha-ketoglutarate dehydrogenase. This enzyme plays a crucial role in the Krebs cycle (also known as the citric acid cycle or TCA cycle).

2. **Understand the Reaction**: Alpha-ketoglutarate dehydrogenase catalyzes the conversion of alpha-ketoglutaric acid to succinyl-CoA. This is an important step in cellular respiration.

3. **Analyze the Chemical Changes**: During this conversion, two significant chemical changes occur:
- **Oxidation**: The alpha-ketoglutaric acid is oxidized, meaning it loses electrons (in this case, hydrogen atoms).
- **Decarboxylation**: One molecule of carbon dioxide (CO2) is removed from alpha-ketoglutaric acid, which is a process known as decarboxylation.

4. **Conclude the Reaction Type**: Since both oxidation and decarboxylation are happening simultaneously in this reaction, we conclude that alpha-ketoglutarate dehydrogenase brings about both oxidation and decarboxylation.

5. **Final Answer**: Therefore, the final answer is that alpha-ketoglutarate dehydrogenase brings about oxidation and decarboxylation.

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