FIG 1.

Characteristics of the alkylated dicyclohexyl carboxylic acid 2CCA-1. (A) Structure of 2CCA-1. (B and D) Optical density measurement and (C and E) viability determination characterizing the lysis curve of (B and C) S. pneumoniae D39 wild-type and (D and E) D39ΔlytA (grown in the presence of 110 mM choline chloride) treated with 2CCA-1 (12.5 μM) compared to penicillin (0.06 μg/ml) or DMSO (1% [vol/vol]) as the solvent control. Arrows indicate time of compound addition. Optical density measurements of a representative experiment are shown as averages ± SD from technical triplicates. Viability data are shown as averages ± SD from three biological replicates. (F) Overview of whole-genome sequenced 2CCA-1-resistant Tigr4 derivative strains (BHN848 to BHN852) displaying locations of single-nucleotide polymorphisms (green) and deletions (red) and (G) the respective D39 derivative 2CCA-1-resistant strains (BHN857 to BHN860 and BHN870). The observed genetic changes of the resistant strains highlighted are described in detail in Table 1.