EFFECTS OF ANTIMYCOTICS ON THE BIOSYNTHESIS OF CELLULAR MACROMOLECULES IN ASPERGILLUS-NIGER PROTOPLASTS

The effects of nine antimycotics on the biosynthesis of cellular macro molecules were analyzed using the regenerating system of protoplasts o f Aspergillus niger. The incorporation of several specific radioactive precursors into major cellular components were measured in the presen ce or in the absence of respective agents. Miconazole, ketoconazole, a nd tolnaftate inhibited the lipid synthesis. 5-Fluorocytosine strongly inhibited the DNA and protein syntheses. Griseofulvin, however, speci fically inhibited the synthesis of cell wall polysaccharides, i.e. chi tin and glucan. Other agents showed non-specific inhibition effects. T he significance of morphological change of hypha as an indicator of an timycotic action and its feasibility as a screening tool for novel ant imycotic compounds are discussed.