Abstract
Lactate dehydrogenase was purified from the eel liver. The molecular weight of the enzyme was determined to be 33, 000 by SDS-polyacrylamide gel electrophoresis. After starch gel electrophoresis the lactate dehydrogenase of the eel liver was seen at the same position of lactate dehydrogenase of the eel heart. The liver lactate dehydrogenase was most resistant to temperature compared to that of liver, heart, and skeletal muscle enzymes. The optimum concentrations of pyruvate and lactate of the eel liver enzyme were 1 and 25mm, respectively. These values were lower than those of skeletal muscle lactate dehydrogenase. In the presence of 1 rust pyruvate and NAD+ the activity of the liver lactate dehydrogenase was inhibited by 70 %, whereas the activity of the skeletal muscle enzyme was inhibited only by 9 %.
These results suggest that the lactate dehydrogenase of the eel liver was heart type. The role of the lactate dehydrogenase on gluconeogenesis in the eel liver was also discussed.
