CYTOCHEMICAL AND ULTRASTRUCTURAL STUDIES OF THE CELL-WALL OF CANDIDA-ALBICANS .1. LOCALIZATION OF MANNAN BY MEANS OF CONCANAVALIN-A ON ULTRATHIN SECTIONS

The ultrastructural localization of polysaccharides in the cell wall of Candida albicans was carried out by means of Concanavalin A on glycol methacrylate ultrathin sections. The sections were incubated successively with horseradish peroxydase, 3-3′ diaminobenzidine and H2O2, for revealing the binding sites of the lectin. This method allowed us to localize mannan, since Concanavalin A does not react with other polysaccharides of the C. albicans cell wall. In these conditions mannan was found to be located in two continuous reactive layers at the periphery of blastospores cell wall. The results are discussed in relation with those obtained by another method using the polysaccharide detection technique described by Thiery (PATAg). © 1979 Springer-Verlag.