Figure 2: Biochemical evaluation by in vitro kinase assay of the FBS hits (F1 and F2) and their analogues (F1.1 to F1.9, and F2.1 to F2.10).

(A) First, the autophosphorylation inhibitory activity was evaluated in a one concentration (2mM) one time-point (30 sec) in vitro kinase assays with WalK and PhoRE. The fragments inhibited WalK and PhoRE autophosphorylation with 10 to 62% and 17 to 80%, respectively. (B) IC50 of the more potent inhibitors (% inhibition at 2 mM > 50%) with antibacterial effect were measured in a multiple-concentrations one time-point (30 sec) experiments.