ACID-PHOSPHATASE-ACTIVITY IN PISOLITHUS-ARRHIZUS MYCELIUM TREATED WITH CADMIUM DUST

The influence of cadmium dust (containing lead, cadmium, copper, zinc, silicium and other elements) on acid phosphatase activity of Pisolith us arrhizus was observed by means of electron microscopy. Dust-treated mycelium showed increased activity of the enzyme, especially on the s urface of the cell wall. There was an increase in abundance of autopha gic vacuoles marked by a strong phosphatase reaction. An increase in t he number of hyphae with diffuse enzyme activity within the cytoplasm coincided with a decrease of life-span of the fungus, rapid changes in the mictoplasm stage, earlier closing of the dolipori and presumably the earlier autolysis of cell cytoplasm. Hyphae showing strong autolyt ic activity were separated from other hyphae by the material deposited within the doliporus and this whole area was devoid at the stage of a cid phosphatase activity. The role of the enzyme in the mechanism of r esistance to toxic elements is discussed.