Fungal β-Glucan Masking Protocols

Strains used in this study are listed in Table S1 in the supplemental material. Strains were cultured routinely on YPD agar (1% yeast extract, 2% Bacto peptone, 2% glucose, and 2% Bacto agar) at 30°C. For β-glucan masking experiments, strains were grown at 30°C, 200 rpm, overnight in yeast nitrogen base without amino acids (BD Difco; 6.7 g/liter) containing the appropriate supplements, plus 2% glucose (YNB-Glu) and then diluted to an OD₆₀₀ of ∼0.1 in fresh YNB-Glu with and without 2% d/l-lactate (Sigma) and grown 5 h at 30°C, 200 rpm. To prepare hypoxic cultures, cells were inoculated into YNB-Glu in a screw-cap conical flask under nitrogen (16 (link)). Cells treated with castanospermine (Cayman Chemical) were grown as described above for β-glucan masking experiments with the addition of castanospermine (in dimethyl sulfoxide [DMSO]) to a final concentration of 1 μM.