SPECTRUM OF ELECTROPHORETIC VARIANTS OF GLUCOSE-6-PHOSPHATE-DEHYDROGENASE, 6-PHOSPHOGLUCONATE DEHYDROGENASE AND GLUCOSE-DEHYDROGENASE IN AMEBAS CULTURED AT DIFFERENT TEMPERATURES

In Amoeba proteus (strain B) the primary cell thermoresistance decreases with the fall of the cultivation temperature within the range of tolerant temperatures from 28 to 4-degrees-C. Alongside, during the fall from 25 to 10-degrees-C, the thermotolerance of Triton-soluble glucose-6-phosphate dehydrogenase (G6PD) not only does not decrease but even increases insignificantly. Hence, changes in the primary cell thermoresistance in amoebae cultured at different temperatures do not correlate with the changes in thermotolerance of this enzyme. Acclimation of amoebae cultured at 25-degrees-C to a relatively low temperature (10-degrees-C) is accompanied with an increase in the total activities of Triton-soluble G6PD, 6-phosphogluconate dehydrogenase (6PGD) and glucose dehydrogenase (GlcDH) per cell, with an increase in GlcDH activity per unit of cellular protein, and with changes in the activity and thermoresistance of some G6PD electromorphs. No differences in the number of G6PD, 6PGD and GlcDH electromorphs found were observed in amoebae cultured at 10 or 25-degrees-C.