Aspartate aminotransferase (AST/GOT) catalyzes the transfer of the amino group from aspartate to alpha-ketoglutarate, forming glutamate and oxaloacetate. The latter is reduced to malate by malate dehydrogenase (MDH) in the presence of reduced nicotinamide adenine dinucleotide (NADH). The reaction is kinetically monitored at 340 nm by the decrease in absorbance resulting from the oxidation of NADH to NAD+, proportional to AST activity in the sample.
