It is activated by pyridoxal or pyridoxamine phosphate. Inhibitors include maleate, succinate, glutarate and adipate.
Aspartate aminotransferase is ubiquitous in mammalian tissues and most abundant in heart muscle.
The enzyme is implicated in maintaining the balance of the four metabolites which are its substrates. In solution the enzyme may be stabilized with a-ketoglutarate and EDTA in maleate or succinate buffers. One unit oxidizes on micromole of NADH per minute at 25deg. C and pH 7.4 using a coupled reaction with malate dehydrogenase. Serum Glutamic Oxalacetic Transaminase Activity.