Aspartate Aminotransferase [Glutamate oxaloacetate transaminase] is a ubiquitous pyridoxal phosphate-dependent enzyme which exists in both mitochondrial and cytosolic forms. The enzyme plays an important role in amino acid metabolism and in the urea and tricarboxylic acid cycles. The 2 isoenzymes are homodimeric. In liver about 80% of the enzyme activity is mitochondrial in origin, whereas in serum the enzyme activity is largely cytosolic. Although the mitochondrial and soluble forms of GOT