FIGURE 4.

Evaluation of the various C. albicans effectors mediating mixed biofilm formation. (A) Based on measurement of fluorescence emitted from GFP-S. mutans, significantly higher fluorescence intensity was detected in mixed biofilms (Sm+Ca) compared to that in S. mutans single biofilm (Sm); similarly, matrix supplementation resulted in a matrix dose-dependent increase in fluorescence, but not supplementation with β-Glucan or α-Mannan (0.5 mg/mL, both). Matrix concentrations tested included 0.5, 1.25, and 0.125 mg/mL. (B) To evaluate the role of C. albicans secreted matrix polysaccharides in mediating S. mutans retention, S. mutans single biofilms were grown in cell-free spent media from the C. albicans strains. Based on measurement of emitted fluorescence from 24 h S. mutants biofilms, significantly higher S. mutans signal was detected from biofilms grown in spent media (Sm+Spent) compared to that from the S. mutans alone. The observed increase in emitted fluorescence from S. mutans biofilms grown in C. albicans spent media was significantly diminished upon enzymatic digestion of the secreted polysaccharides in the media by α-mannosidase (0.5, 1, and 2 U/mL) and β-glucanase (1,25, 2.5, and 5 U/mL) enzymes with α-mannosidase treatment being more impactful. Statistical comparison between Sm alone and Sm + spent is indicated with a black bar. Comparative analysis between Sm biofilm in digested-spent media versus Sm + spent is indicated with a blue bar. ns: not significant; **p ≤ 0.01; ***p ≤ 0.005; ****p ≤ 0.001.