Each amino transferase is specific for one or at most a few amino group donors. Amino transferases are named after the specific amino group donors because the acceptor of the amino acid is almost always α-ketoglutarate. The most important amino transferase reactions are catalysed by alanine amino transferase or serum glutamate pyruvate transaminase (SGPT) and aspartate amino transferase (AST) or serum glutamate oxaloacetate transaminase (SGOT).