Purification and properties of cytoplasmic malate dehydrogenase from Taenia crassiceps (Zeder, 1800) cysticerci.

Malate dehydrogenase (L-malate: NAD oxidoreductase, EC 1.1.1.37) from the cytoplasm of Taenia crassiceps cysticerci was purified and the basic kinetic parameters of this enzyme were determined. The pH optimum range of enzyme reaction was found to be very wide: 8.8-11.0 for malate oxidation and 6.0-8.5 for oxaloacetate reduction. KM values for oxaloacetate, malate, NAD, and NADH were 7.8.10(-5) M, 1.4.10(-4) M, 1.2.10(-4) M, and 6.10(-5) M, respectively. Malate dehydrogenase activity was inhibited by malate excess. Molecular weight of malate dehydrogenase was 70,800. A comparison of the data obtained with those from other organisms including vertebrates showed that the cytoplasmic malate dehydrogenase from T. crassiceps is almost identical with the enzymes from other sources in its kinetic and regulatory properties, as well as in its molecular weight.