Subcellular Distribution, and Physical and Immunological Properties of Hepatic Alanine: Glyoxylate Aminotransferase Isoenzymes in Different Mammalian Species

1. Subcellular distribution, and physical and immunological properties of hepatic alanine: glyoxylate aminotransferase isoenzymes 1 and 2 were examined with ten different mammalian species. 2. Intracellular organelles containing isoenzyme 1 varied from species to species; isoenzyme 1 was located in the peroxisomes, mitochondria or both organelles. In contrast, isoenzyme 2 was found only in the mitochondria but not in the peroxisomes. 3. In any species, isoenzyme 1 had molecular weight of approx. 80,000 with two identical subunits, and isoenzyme 2 approx. 200,000 with four identical subunits. 4. In any species, an immunological cross-reactivity was observed among isoenzymes 1 and among isoenzymes 2 but did not between isoenzymes 1 and isoenzymes 2.