FIG 1.

Levels of detectable exo-GXM negatively correlate with capsule thickness under a variety of medium conditions. To generate conditioned medium, we normalized 24-h cultures by cell density and then passed the supernatants through a 0.22-μm-pore-size filter to remove fungal cells. (A) Representative image of cell/capsule measurements used in this study. (B) We tested supernatants for free GXM (exo-GXM) by blotting and probing samples with the F12D2 anti-GXM MAb. See Materials and Methods for further details. A representative blot showing relative levels of exo-GXM collected from cells cultured for 24 h under a variety of capsule- and non-capsule-inducing conditions is shown. (C) The intensities of exo-GXM bands relative to those of exo-GXM in YNB–2% glucose cultures (blue bars) were quantitated for three independent experiments and plotted next to absolute measurements of capsule thickness (yellow bars) (n = 30 cells). Data were combined from three independent experiments. Bars represent the means, and error bars represent the standard deviations. Sab, Sabouraud's medium.