Figure 1
APT-6K is a copper specific bactericide that rapidly reduces ATP levels. (a) Structure of APT-6K. The green circle denotes the NNSN motif. (b) Activity of APT-6K against S. aureus strain Newman in media supplemented with 50 µM copper (Cu) (blue circles), cobalt (Co), manganese (Mn), nickel (Ni), zinc (Zn), or iron (Fe). (c) APT-6K and Cu were titrated against each other in a microplate assay and bacterial growth of the S. aureus strain Newman was determined after 20 hours. (d) Culture samples from each condition of the microplate assay in (d) were transferred into drop assays to determine whether any observed growth inhibition in (d) had been bacteriostatic (outgrowth) or bactericidal (no outgrowth) in nature. Results for inactive copper concentrations below 2.5 µM were removed from the presentation. (e) Time to kill kinetics of S. aureus strain Newman exposed to increasing concentrations of APT-6K in the presence of 50 µM Cu. (f) ATP levels in S. aureus strain Newman after exposure for one hour to APT-6K + 50 µM Cu or CCCP, a mitochondrial oxidative phosphorylation uncoupler. All values were normalized to the untreated controls of each series.
