Transamination reactions are central to amino acid catabolism. Pyridoxal phosphate (PLP) is the essential cofactor for aminotransferases. In the alanine aminotransferase (ALT) reaction, alanine donates its amino group to alpha-ketoglutarate. What are the two products of this reaction?
- A Oxaloacetate and aspartate
- B Pyruvate and glutamate ✓
- C Pyruvate and aspartate
- D Alpha-ketoglutarate and alanine
Correct answer: B. Pyruvate and glutamate
Explanation
ALT (alanine aminotransferase) catalyzes: alanine + alpha-ketoglutarate → pyruvate + glutamate. The amino group from alanine is transferred to alpha-ketoglutarate forming glutamate, while alanine's carbon skeleton becomes pyruvate. ALT is liver-specific in clinical use; elevated serum ALT indicates hepatocellular damage. Pyruvate can then enter gluconeogenesis or the TCA cycle.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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