Journal: Antimicrobial Agents and Chemotherapy
Article Title: Failures in Clinical Treatment of Staphylococcus aureus Infection with Daptomycin Are Associated with Alterations in Surface Charge, Membrane Phospholipid Asymmetry, and Drug Binding
doi: 10.1128/aac.00719-07
Figure Lengend Snippet: FIG. 2. Membrane depolarization by daptomycin, RP-1, and Triton X-100 by flow cytometry at 60-min exposures. These data represent the means for three separate assays. See the text for details.
Article Snippet: Calcein-loaded S. aureus cells (final inoculum, 106 CFU/ml) were diluted into the sublethal concentrations of test AP or daptomycin solutions (i.e., 0.5 g/ml tPMP-1, 10 g/ml hNP-1, 32 g/ml gramicidin D, and 1.5 g/ml daptomycin) based on our pilot studies and incubated at 37°C for 120 min. At selected time points, calcein retention was quantified using a Turner digital fluorometer (model 450; Barnstead/Thermolyne Corp., Dubuque, IA) (49).
Techniques: Membrane, Cytometry