COUMARIN-INDUCED DISTURBANCES OF MORPHOLOGICAL DEVELOPMENT AND CELL-WALL FORMATION IN TRICHOPHYTON MENTAGROPHYTES

Abstract

When T. mentagrophytes thalli are placed on a medium containing 300 .mu.g/ml of coumarin, their growth rate is drastically reduced. The newly formed mycelium consists of curled and branched hyphae showing subapical bulges and swollen tips. Under EM, the most relevant abnormalities concern the cell walls, which are often thickened by aberrantly-shaped zones that are usually smeared unevenly over the surface of the primary wall instead of being deposited in discrete ridges. An ultracytochemical analysis suggests that the irregular thickenings are made of chitin. Arguments to explain these phenomena are discussed.