Identification of heparin‐binding proteins expressed on Trichosporon asahii cell surface

Abstract

AbstractTrichosporon asahii is a pathogenic yeast that cause trichosporonosis. T. asahii exhibits several colony morphologies, such as white (W)‐ or off‐white (O)‐type, which may affect virulence. In this study, we compared the expression pattern of heparin‐binding proteins in various colony morphologies and identified heparin‐binding protein in T. asahii. Surface plasmon resonance analysis revealed that cell surface molecules attached more strongly to heparin in W‐ than O‐type cells. We purified and identified a heparin‐binding protein strongly expressed in W‐type cells using heparin‐Sepharose beads, named it heparin‐binding protein 1 (HepBP1), and expressed Flag‐tagged HepBP1 in mammalian cells. The heparin‐binding ability of Flag‐tagged HepBP1 was confirmed by pulldown assay using heparin‐Sepharose beads. Thus, HepBP1 is a heparin‐binding protein on T. asahii cell surface. These results suggest that several T. asahii cell surface proteins interact with glycosaminoglycans; therefore, they could contribute to infection.