FIG 1 .

Assessment of relative biomass and vancomycin susceptibility in single S. aureus (SA) and mixed S. aureus and C. albicans (SA/CA) biofilms. (A) Preformed (24-h) S. aureus single and mixed biofilms were treated with vancomycin (800 µg/ml) for an additional 24 h. CFU recovery of S. aureus from both biofilms showed a significant increase in S. aureus recovery from mixed biofilms following vancomycin treatment (***, P < 0.001). (B) To assess biomass, 24-h single- and mixed-species biofilms were treated with crystal violet. Based on absorbance (595 nm), results demonstrated significantly higher biomass for mixed biofilms than for S. aureus biofilm (**, P < 0.01; ***, P < 0.001). Means and standard errors of the means are shown. (C and D) These results were corroborated by SEM analysis where images demonstrated adherence to and clumping of S. aureus around C. albicans hyphae, forming thick biofilm aggregates.