Figure 4.

Synergistic effect of DA7 and LysK against S. aureus biofilms in static and dynamic models. (A) SA113 biofilms grown statically in 96-well plates were treated with two-fold serial dilutions of DA7, LysK, and mixtures of both enzymes at the ratios 50:50, 75:25, and 25:75, with the highest concentrations on the right and the lowest concentrations on the left of each row. After treatment, residual biofilms were stained with crystal violet. For each individual enzyme, the highest concentration used was the respective minimum biofilm eradication concentration (MBEC) and was defined as 100%. Highest concentrations of enzymes within mixtures are expressed as percentages of the respective MBECs. (B) Residual viable S. aureus on the glass surface of the Biostream flow cell after a 2 h treatment of dynamic biofilms with buffer (control), DA7 (0.625 nM), LysK (1.25 µM), or a combination of both (0.156 nM DA7 + 0.938 µM LysK, corresponding to a ratio of 25:75). Error bars represent standard deviations from at least seven independent experiments. Bars with different letters are significantly different from each other (p < 0.05).