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 Pisolithus arrhizus was observed by means of electron microscopy. Dust-treated mycelium showed increased activity of the enzyme, especially on the surface of the cell wall. There was an increase in abundance of autophagic vacuoles marked by a strong phosphatase reaction. An increase in the number of hyphae with diffuse enzyme activity within the cytoplasm coincided with a decrease of lifespan 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 autolytic activity were separated from other hyphae by the material deposited within the doliporus and this whole area was devoid at that stage of acid phosphatase activity. The role of the enzyme in the mechanism of resistance to toxic elements is discussed.