Surface proteinaceous fibrils (fimbriae) on filamentous fungi

Abstract

Proteinaceous fibrils (fimbriae) of 4–10 nm diam. have been described in several lower eukaryotes, including yeast-like fungi and certain algae. Antibodies prepared against the fimbriae of Ustilago violacea cross react with antigens present on the surface of these same organisms. In this paper we extend these observations to a diverse group of filamentous fungi, representing the major groups. These fungi also produce surface fibrils of 6–10 nm diam. and have surface antigens that cross react with the antibodies of U. violacea fimbriae. We conclude that surface proteins of a conserved type are common in the lower eukaryotes and that these may be manifested as surface fibrils of 4–10 nm diam. In some organisms these are extruded as numerous very long fimbriae (up to 30 μm); in others they may remain largely embedded in the wall or appear as a short fringe or as sparse longer fibrils.