Definition check — what is oxidative deamination? Oxidative deamination is best described as the conversion of an amino acid into which set of products?

Introduction / Context:
Oxidative deamination removes an amino group from an amino acid while oxidizing the carbon skeleton, typically generating a corresponding alpha-keto acid and free ammonia. This reaction is central to hepatic nitrogen disposal and integration with the tricarboxylic acid cycle via alpha-ketoglutarate and other intermediates.

Given Data / Assumptions:

• Glutamate dehydrogenase is the prototypical enzyme catalyzing oxidative deamination.
• NAD+ or NADP+ accepts electrons in the process.
• Free ammonia is produced for conversion to urea in the liver.

Concept / Approach:

Differentiate oxidative deamination from transamination. Transamination transfers amino groups between amino acids and alpha-keto acids without releasing ammonia. Oxidative deamination releases ammonia and produces a keto acid from the original amino acid carbon skeleton.

Step-by-Step Solution:

Verification / Alternative check:

Enzymatic assays for glutamate dehydrogenase demonstrate stoichiometric production of NH3 and alpha-keto acids, confirming the definition.

Why Other Options Are Wrong:

Option A describes transamination, not oxidative deamination. Options B and E propose products (carboxylic acid or aldehyde) that are not standard outcomes. Option D misconstrues the chemistry.

Common Pitfalls:

Mixing up “transfer” (transamination) with “release” (oxidative deamination) of ammonia.

Final Answer:

Amino acid converted to a keto acid plus ammonia