title: Force nanoscopy of hydrophobic interactions in the fungal pathogen Candida glabrata.
abstract: Candida glabrata is an opportunistic human fungal pathogen which binds to surfaces mainly through the Epa family of cell adhesion proteins. While some Epa proteins mediate specific lectin-like interactions with human epithelial cells, others promote adhesion and biofilm formation on plastic surfaces via nonspecific interactions that are not yet elucidated. We report the measurement of hydrophobic forces engaged in Epa6-mediated cell adhesion by means of atomic force microscopy (AFM). Using single-cell force spectroscopy, we found that C. glabrata wild-type (WT) cells attach to hydrophobic surfaces via strongly adhesive macromolecular bonds, while mutant cells impaired in Epa6 expression are weakly adhesive. Nanoscale mapping of yeast cells using AFM tips functionalized with hydrophobic groups shows that Epa6 is massively exposed on WT cells and conveys strong hydrophobic properties to the cell surface. Our results demonstrate that Epa6 mediates strong hydrophobic interactions, thereby providing a molecular basis for the ability of this adhesin to drive biofilm formation on abiotic surfaces.
authors.affiliation: Institute of Life Sciences, Université Catholique de Louvain , Croix du Sud, 1, bte L7.04.01, B-1348 Louvain-la-Neuve, Belgium.
authors.forename: Sofiane
authors.initials: S
authors.lastname: El-Kirat-Chatel
authors.forename: Audrey
authors.initials: A
authors.lastname: Beaussart
authors.forename: Sylvie
authors.initials: S
authors.lastname: Derclaye
authors.forename: David
authors.initials: D
authors.lastname: Alsteens
authors.forename: Soňa
authors.initials: S
authors.lastname: Kucharíková
authors.forename: Patrick
authors.initials: P
authors.lastname: Van Dijck
authors.forename: Yves F
authors.initials: YF
authors.lastname: Dufrêne
mesh_terms: D018441:Biofilms / Q000254:growth & development; D041221:Candida glabrata / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D002448:Cell Adhesion; D005656:Fungal Proteins / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D018625:Microscopy, Atomic Force; D036103:Nanotechnology / Q000379:methods*; D059010:Single-Cell Analysis; D013499:Surface Properties
chemical_list: D005656:Fungal Proteins
keywords: Candida glabrata; Epa6; adhesion; atomic force microscopy; chemical force microscopy; fungal pathogens; hydrophobic forces; single-cell force spectroscopy