MURAMIDASE-MEDIATED DAMAGE TO CANDIDA YEAST-CELLS - HISTOCHEMICAL ANDIMMUNOCHEMICAL CHARACTERIZATION OF ACCUMULATING WALL-LIKE MATERIAL

Hen egg-white lysozyme is known to be fungicidal to blastoconidia of C andida albicans under defined in vitro conditions. This lethal action leads to changes in the layering of cell wall and to plasmolysis, caus ed by unremitting accumulation of wall-like material between the yeast cell wall and cytoplasmic membrane. Here, several methods were applie d on ultrathin sections to define the nature of wall-like material: hi stochemical staining with periodic acid-thiocarbohydrazide-silver prot einate, periodic acid-alkaline bismuth, and phosphotungstic acid at lo w pH; the localization of carbohydrate residues with lectin-gold compl ex; immunocytochemical staining with monospecific antibodies, factor 1 and 6, which recognized major cell wall antigens, The wall-like mater ial was almost uniformly highlighted with periodic acid-thiocarbohydra zide-silver proteinate, factor 1 antibody, concanavalin A-gold and whe at germ agglutinin-ovomucoid-gold, indicating the presence of mannopro teins and chitin. The serotype A-specific epitope recognized by factor 6 antibody was not detected in the wall-like material, although it wa s demonstrated in the outer cell wall layers after 2 h of exposure to lysozyme.