Figure 3

Influence of cell wall thickness on mersacidin activity. The influence of an increased cell wall thickness on the efficacy of mersacidin was studied for the S. aureus strains SA137/93A (A), SA137/93G (B) and SG511 (C). To this end, S. aureus cells were incubated in resting medium supplemented with glucose (RM+g), which allows the synthesis of increased amounts of peptidoglycan, or in the absence of glucose (RM-g), which prevents synthesis of extra cell wall material. The data represent the optical density (600 nm) of RM-preincubated S. aureus cells after treatment with different concentrations of mersacidin. Vancomycin served as a control. Black triangle, mersacidin/RM+g; white triangle, mersacidin/RM-g; black square, vancomycin/RM+g; white square, vancomycin/RM-g.