Overexpression of <i>uge3</i> or <i>ugeB</i> in <i>A</i>. <i>nidulans</i> increases the GalNAc content of GAG and enhances the formation of adherent biofilms.

<p>(A) Relative expression of <i>uge3</i> in the An-Uge3 strain and <i>ugeB</i> in the An-UgeB strain compared to the expression level of <i>ugeB</i> in wild-type <i>A</i>. <i>nidulans</i> grown in Brian medium and as measured by real-time RT-PCR. (B) Total amount of secreted GAG from the indicated strains. (C) GalNAc content of secreted GAG from the indicated strains as determined by gas chromatography and quantified by hexose or hexosamine assays. (D) Cell wall GalNAc staining with FITC-conjugated soybean agglutinin (SBA). SBA binding to mature hyphal mats of the indicated strains was quantified by fluorometry. (E) Scanning electron micrograph of hyphae of indicated species at 20,000X magnification. Arrows indicate surface decorations associated with cell wall-bound GAG. (F) Formation of adherent biofilms on tissue culture treated polystyrene plates by the indicated strains. After 24 hours growth, biofilms were washed and visualized by staining with 0.1% crystal violet. (G) Detection of β-1,3-glucan exposure on the surface of hyphae by immunostaining with Fc-dectin-1 antibody labeled with FITC secondary antibody and quantified by fluorometry at 495 nm. For all panels: An-Uge3 indicates the <i>A</i>. <i>nidulans</i> overexpressing <i>uge3</i> strain; An-UgeB indicates the <i>A</i>. <i>nidulans</i> overexpressing <i>ugeB</i> strain; and AnWT indicates wild type <i>A</i>. <i>nidulans</i>. Data are represented as mean +/- SEM and * indicates a significant difference between <i>A</i>. <i>nidulans</i>, and both overexpression strains, p<0.05 by ANOVA with Tukey’s test for pairwise comparison.