Plays a key role in amino acid metabolism. Important for metabolite exchange between mitochondria and cytosol (By similarity). 2-oxoglutarate + L-aspartate = L-glutamate + oxaloacetate Homodimer. In eukaryotes there are cytoplasmic, mitochondrial and chloroplastic isozymes. Belongs to the class-I pyridoxal-phosphate-dependent aminotransferase family.