THE CELL WALL-ASSOCIATED GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE OF CANDIDA-ALBICANS IS ALSO A FIBRONECTIN AND LAMININ-BINDING PROTEIN

By immunoelectron microscopy with a polyclonal antibody against the cy tosolic glycolytic enzyme glyceralde-hyde-3-phosphate dehydrogenase (G APDH) from Candida albicans (anti-GAPDH PAb), the protein was clearly detected at the outer surface of the cell wall, particularly on blasto conidia, as well as in tie cytoplasm, Intact blastoconidia were able t o adhere to fibronectin and laminin immobilized on microtiter plates, and this adhesion was markedly reduced by both the anti-GAPDH PAb and soluble GAPDH from Saccharomyces cerevisiae. In addition, semiquantita tive flow cytometry analysis with the anti-GAPDH PAb showed a decrease in antibody binding to cells in the presence of soluble fibronectin a nd laminin, Purified cytosolic C. albicans GAPDH was found to bind to fibronectin and laminin in a ligand Western blot assay. These observat ions suggest that the cell wall-associated form of the GAPDH in C. alb icans could be involved in mediating adhesion of fungal cells to fibro nectin and laminin, thus contributing to the attachment of the microor ganism to host tissues and to the dissemination of Candida infection.