Enzyme Activity Pattern and Mitochondrio-cytoplasmic Relations in Protozoa. Comparative Study of Tetrahymena pyriformis, Allogromia laticollaris, and Labyrinthula coenocystis

SYNOPSIS. Enzyme activity patterns were determined in Tetrahymena pyriformis, Allogromia laticollaris , and Labyrinthula coenocystis. The activities of enzymes belonging to certain metabolic pathways (glycolysis, fatty acid oxidation, tricarboxylic acid cycle) had constant proportions in each species, whereas their absolute levels differed. The activities of intramitochondrial enzymes were compared with the mitochondrial to total cytoplasmic volume ratio. Despite the very different fine structure of the mitochondria in the 3 protozoa, there was good correlation between the activities of citric acid cycle enzymes and the mitochondrial volume.