Question

Aminotransferases are a family of enzymes that have important roles in amino acid metabolism and nitrogen metabolism. Aminotransferases catalyze a transamination reaction between an amino acid and an α-keto acid (see the reaction below).

What two amino acids can be converted to an intermediate in the citric acid cycle by tranamination?



A. Arg and Lys B. Ser and Thr C. Val and Met D. Asp and Glu E. Tyr and Phe

Answer 1

The two amino acids that can be converted to an intermediate in citric acid cycle by transamination are:-

Aspartate (Asp) and Glutamate (Glu).

Aspartate + - Ketoglutarate <======> Oxaloacetate + Glutamate

The reaction is carried out by enzymes :-

• Aspartate Aminotransferase or
• Glutamate Oxaloacetate transferase

Both Oxaloacetate and - Ketoglutarate are intermediates of citric acid cycle.