Figure 1: Impact of bacteriostatic and bactericidal antibiotics at F10 concentrations.
From: Microscale insights into pneumococcal antibiotic mutant selection windows
(a,b) Plate reader assays measuring cell density (closed symbols, OD595) and gene expression (symbols without outline, RLU, relative luminescence unit, a.u.) of S. pneumoniae D-PEP22 (that constitutively expresses luciferase) growing in the presence of concentration series of a typical bacteriostatic (tetracycline, a) and a typical bactericidal (trimethoprim, b) antibiotic; experimental duplicates are shown and all experiments were replicated at least three times. (c,d) Comparison of cell density and gene expression kinetics during treatment with bacteriostatic (c) and bactericidal (d) antibiotics at F10 concentrations (allowing for OD increase in treated cultures of a factor 10 within 10 h of cultivation). CHL, chloramphenicol; CIP, ciprofloxacin; ERY, erythromycin; KAN, kanamycin; RIF, rifampicin; STR, streptomycin; TET, tetracycline; TMP, trimethoprim. (e,f) Development of the count of viable cells (CFUs ml−1) during F10 treatment; average values of duplicates are shown. (g) Overlay of phase contrast and fluorescence microscopy of Hoechst DNA-stained D-PEP22 taken from 1 h (upper panel) and 6 h (lower panel) of F10 treatment. Scale bar, 4 μm.
