Fig 2. Lysostaphin and nisin kill MRSA persisters by inducing membrane permeabilization.

MRSA persisters were treated with 0.1% DMSO (A), 10X MIC lysostaphin (B), or 10X MIC nisin (C). Membrane permeabilization (open circles) was measured spectrophotometrically by monitoring the uptake of SYTOX Green (excitation wavelength of 485 nm and an emission wavelength of 525 nm). Colony forming unit counts of persisters (solid circles) were measured by serial dilution and plating on TSA plates. The data points on the x-axis are below the level of detection (2x10² CFU/mL). Results are shown as means ± s.d.; n = 3.