Oxidoreductive and hydrolytic enzyme patterns in plant suspension culture cells: Local and time relationships

Abstract

1. 1. Cytochemical tests were used to determine the patterns of enzyme activities in WR-132 suspension cultures. A geometrical periodicity was observed in 3-day-old cells for several dehydrogenases. The pattern was three negative cells to one positive cell for malate and succinate dehydrogenase, but the reverse for ethanol and 3-hydroxybutyrate dehydrogenase. Enzymes which did not demonstrate this periodicity in 3-day-old cells were acetylesterase, acid phosphatase, and cytochrome oxidase. 2. 2. On the basis of cytochemical localization enzyme activity was assigned to specific intracellular sites for the following: acetylesterase in endoplasmic reticulum, acid phosphatase in cell wall, glucose-6-phosphate dehydrogenase in spherosomes and lipid-rich particles, succinate dehydrogenase in plastidlike structures as well as in mitochondria, glutamate dehydrogenase in particles heavily concentrated within cytoplasmic regions adjacent to the cross-wall. 3. 3. Spectrophotometric analyses of formazan extracts obtained following dehydrogenase reactions demonstrated that specific enzyme activity in the cell cultures oscillated over the 12-day growth period. Four activity profiles were obtained for the six dehydrogenases examined. The data suggested a correlation between succinate and glutamate dehydrogenase and also ethanol and 3-hydroxybutyrate dehydrogenase. The maxima and minima in the activity curve for malate dehydrogenase were distinct.