STUDY OF SUPRAMOLECULAR STRUCTURES RELEASED FROM THE CELL-WALL OF CANDIDA-ALBICANS BY ETHYLENEDIAMINE TREATMENT

Candida albicans cell wall components were analyzed by ethylenediamine (EDA) treatment. Based on their different solubility properties, the cell wall components produced three fractions (A, B, and C). Fractions B (EDA-soluble, water-insoluble) and C (EDA-insoluble) contained gluc an: chitin, and protein in different proportions. After zymolyase (mai nly a beta-glucanase complex) or chitinase treatment of fractions B an d C, more polysaccharides and proteins were solubilized by a second ED A treatment, suggesting that the solubility of the polymers in EDA dep ends on the degree of polymer inter-actions. Western blot analysis usi ng two monoclonal antibodies (1B12 and 4C12) revealed electrophoretic patterns that were similar in mycelial and yeast morphologies, except that in material obtained from mycelial walls, an additional band was detected with MAb 1B12. Fluorescence microscopy of cell wall fractions treated with FITC-labeled Con-A, Calcofluor white, and FITC-labeled a gglutinin showed that glucan and mannoproteins are uniformly distribut ed in fractions B and C, while chitin is restricted to distinct patche s. Transmission electron microscopy demonstrated that fraction C maint ained the original shape of the cells, with an irregular thickness gen erally wider than the walls. When fraction C was treated with chitinas e, the morphology was still present and was maintained by an external glucan layer, with an internal expanded fibrillar material covering th e entire cellular lumen. Degradation of the glucan skeleton of fractio n C with zymolyase resulted in the loss of the morphology.