Several cell wall proteins released from yeast and hyphal cells of Candida albicans by laminarinase reacted with an affinity-purified antiserum raised against beta-1,6-glucan. Binding of the antiserum was competitively inhibited by beta-1,6-glucan, but not by beta-1,3-glucan or isolated N-chains. Immunodetection was completely abolished when the proteins were treated with periodate. These results demonstrate that the laminarinase-released wall proteins of C. albicans possess an epitope consisting of beta-1,6-linked glucose residues. The yeast form of C. albicans contained four beta-1,6-glucosylated wall proteins, an Endo H-resistant protein of 125 kDa and three glycoproteins which became only detectable after Endo H digestion and had a molecular mass of 320, 170 and 44 kDa, respectively. As for the hyphal form, a different set of beta-1,6-glucosylated wall proteins was found consisting of two Endo H-resistant glycoproteins of 125 and 80 kDa, respectively, and two glycoproteins that after Endo H digestion had a molecular mass of 320 and 38 kDa, respectively. Sodium dodecyl sulfate-extractable wall proteins and medium proteins did not react with the beta-1,6-glucan antiserum. The beta-1,6-glucan epitope could be removed by aqueous hydrofluoric acid indicating that the epitope is phosphodiester-linked to the cell wall proteins. It is speculated that the epitope forms part of a GPI-anchor and might be involved in the anchoring of mannoproteins into the cell wall.