ddcP, pstB, and excess D-lactate impact synergism between vancomycin and chlorhexidine against Enterococcus faecium 1,231,410
Fig 2
A ΔddcP mutant has reduced susceptibility to vancomycin/glycine synergy.
(A) E. faecium 410 wild-type and (B) ddcP deletion mutant cultures were grown at 37°C in BHI until OD600 reached 0.6 as described in materials and methods. Equal volumes of cultures were split into BHI (control; red circles) or BHI containing vancomycin (50 μg/ml) and glycine (0.2 M) (green squares). OD600 values were monitored for 6 h and a reading at 24 h was recorded. Error bars indicate standard deviations from n = 3 independent experiments. Significance was assessed using the one-tailed Student’s t-test. * denotes P-value < 0.05. Stars indicate significant differences between vancomycin- and glycine-treated cultures in panel B versus A.