Fig. 1.

Turbidity measurement and assessment of bacterial growth in the presence or absence of LL-37. a-d Turbidity measurements in bacterial cultures in the presence of different concentrations of LL-37 were done with the Bioscreen C instrument. OD values of duplicate cultures were determined every 15 min for a total of 10 h. a Dose-response experiment using LL-37 at concentrations ranging from 0 to 10 μM in cultures of S. pyogenes 5448. The scatter plot shows data obtained after 10 h of culture in 6 independent experiments. OD curves show measurements over time from 1 representative experiment of S. pyogenes 5448 (b) and of E. coli (c) cultures in the absence or presence of either 1 or 10 μM LL-37. d Comparison of OD values obtained after 10 h of 5448 culture in the absence or presence of indicated LL-37 concentrations of 1 and 10 μM after 10 h incubation (7 experiments). e Bacterial CFU/ml were determined immediately after the bioscreen assay had been completed. f After 10 h of 5448 culture in the absence or presence of LL-37, CFU/ml were determined over time (0-24 h). Mean ± SEM of 4 experiments at each time point is shown. Statistical significant differences were determined by ANOVA using the Kruskal-Wallis test and Dunn's multiple comparisons. n.s. = Not significant.