Hypothesis: daptomycin permeabilizes membranes by forming self assembled nanotubes

Abstract

Daptomycin is the only lipopeptide antibiotic that is widely used in clinical practice. It was discovered by Eli Lilly and then studied and commercialized by Cubist Pharmaceuticals in 2003. Although this antibiotic has been used for 17 years, the debate over its mechanism of action is ongoing. In this paper, we discuss the different hypotheses on the mode of action of this antibiotic with a primary focus on the bacterial membrane permeabilization as the main mechanism of action. By comparing the experimental data on the oligomerization of daptomycin in membranes with properties of self-assembling cyclic peptides, we conclude that the structure of daptomycin oligomer should resemble the structures of peptide nanotubes that serve as ion channels in membranes.