Galactose-poor Δuge5 galactosaminogalactan retains normal virulence-associated functions.
A, biofilm adherence of indicated strains after 24 h of growth on polystyrene plates, after several washes, and visualized by staining with crystal violet. B, adherence of germinated hyphae of the indicated strains to A549 epithelial cells after 30 min. C, detection of Fc-dectin-1 binding using immune staining. Conidia from respective strains were grown for 12 h in Brian medium, fixed, blocked, stained with Fc-dectin-1, and FITC-labeled F(ab) fragment, and total fluorescence was measured with Spectramax® fluorescence microplate reader. D, induction of bone marrow-derived dendritic cell apoptosis as determined by caspase-3 activity. Conidia from indicated strains were grown for 9 h in RPMI 1640 medium and then co-incubated with mouse bone marrow-derived dendritic cells at a multiplicity of infection of 10:1. Caspase-3 activity was measured by commercial assay following the manufacturer's instructions (Invitrogen).