The activity and distribution of aspartate aminotransferase (EC 2.6.1.1) and alanine aminotransferase (EC 2.6.1.2) in adult Fasciola hepatica have been studied. Fasciola hepatica was fractionated by differential centrifugation into nuclear, mitochondrial and cytosolic fractions. The activity of GOT and GPT was measured by the method of Reitman and Frankel. Isozyme patterns of those enzyme were also examined by DEAE-cellulose column chromatography. The results obtained were as follows: The activity of aspartate and alanine aminotransferase was about 0.55 unit and 0.92 unit per 1 g of Fasciola hepatica, respectively. The activity of those enzymes was relatively low compared with those in mammalian tissues. The distribution of aspartate aminotransferase in the subcellular organelles showed that 71 percent of the activity was in cytosolic, 24 percent in mitochondrial and 5 percent was in nuclear fraction. About 22 percent of the total alanine aminotransferase activity was found in the mitochondrial fraction, about 66 percent in the cytosolic fraction. Aspartate aminotransferase from cytosolic fraction was separated into two types of isozymes, whereas alanine aminotransferase from cytosolic fraction gave only one active peak on DEAE-cellulose column chromatography.
