Figure 3

Chimeric lysin ClyL and parental phage lysin Lys0859 were used to treat 24-h- and 48-h-old biofilms formed by S. aureus ATCC29213 and S. agalactiae ATCC13813 coinfection. A–C The optimal conditions for dual-species biofilm formation. A The biomass of dual-species (S. aureus ATCC29213 and S. agalactiae ATCC13813) biofilms formed at 37 °C for 24 h. The viable cell counts of dual-species biofilms of S. aureus ATCC29213 (B) and S. agalactiae ATCC13813 (C) formed at 37 °C for 24 h. D The biomass of dual-species biofilms treated with ClyL, Lys0859, or ClyL + Lys0859 at 37 °C for 2 h. E Viable cell counts of dual-species biofilms treated with ClyL, Lys0859, and ClyL + Lys0859 at 37 °C for 2 h. Significant differences between the PBS groups and the ClyL, Lys0859, and ClyL + Lys0859 groups were determined via Student’s t test (ns P > 0.05, * P < 0.05 ** p < 0.01, and *** P < 0.001). Significant differences between the ClyL + Lys0859 groups and the ClyL and Lys0859 groups were determined via Student’s t test (ns P > 0.05, # P < 0.05, ## P < 0.01, and ### P < 0.001). The error bars represent the standard deviations (SD). F FESEM images of dual-species biofilms (48 h) formed by S. aureus ATCC29213 and S. agalactiae ATCC13813. The dual-species biofilms were treated with PBS, ClyL (100 μg/mL), Lys0859 (100 μg/mL), or the phage lysin cocktail ClyL (100 μg/mL) + Lys0859 (100 μg/mL).