ABSTRACT
Trichosporon 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.
Subject(s)
Heparin , Heparin/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Protein Binding , Membrane Proteins/genetics , Membrane Proteins/metabolism , Trichosporonosis/microbiology , Humans , Surface Plasmon Resonance , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Membrane/metabolism , BasidiomycotaABSTRACT
Candida species are opportunistic fungal pathogens that cause superficial or invasive infections. Recently, the incidence of infection by non-Candida albicans species, especially Candida glabrata, has increased. In this study, we analyzed the adhesion and cytotoxicity of various Candida spp. that are part of the normal human microbiota. C. albicans adheres well to cell culture plates and to cultured cells. C. glabrata selectively adheres to epithelial cells rather than to cell culture plates. Candida parapsilosis insufficiently adheres to confluent monolayers of human lung epithelial A549 and keratinocyte HaCaT cells. We then analyzed the cytotoxicity of C. albicans and C. glabrata, which adhered well to epithelial cells. C. glabrata has been found to cause more damage to A549 cells than to HaCaT cells, suggesting that resident Candida spp. have distinct cytotoxic effects in different tissues. It is important to clarify the properties of Candida spp. as there is evidence that normal microbiota can cause infections. Our data suggest that it is necessary to use appropriate cell lines for characterizing the adherence and cytotoxicity of Candida spp.
