Antibacterial activity of synthetic dermaseptins against growing and non-growing Escherichia coli cultures.

We synthesized, and purified to homogeneity, four peptides with sequences corresponding to natural dermaseptins. We compared their in-vitro antibacterial potencies against growing and non-growing Escherichia coli cells under different oxygen conditions. The dermaseptins displayed different antibacterial potencies (MICs = 1-4 microM). Killing assays showed that slowly growing bacteria were more susceptible to the synthetic replicates of dermaseptins than rapidly growing cells. In addition, the peptides displayed high efficacy in strictly anaerobic incubation conditions. These results suggest that synthetic dermaseptins are of potential interest in the eradication of bacteria placed in a dormant state and/or subjected to low oxygen tensions.