The extensive spread of multidrug resistance to Gram-negative bacteria has become a huge threat to human health, where peptide-based antibacterial agents have emerged as a powerful star weapon. Here we report a lipopeptide (LP-20) constructed nanomicelle with a different antibacterial mechanism of membrane curvature modulation, which induced dynamic membrane fission resulting in acceleration and enhancement of antibacterial activity to clinically isolated ESKAPE strains, including multidrug-resistant (MDR) pathogens. The minimum inhibitory concentration was reduced to 2-10 μM, and the minimum duration for killing was shortened to less than an hour by LP-20. This is an improvement over antimicrobial peptides and traditional antibiotics, such as ciprofloxacin and tetracycline, significantly enhancing antibacterial activity for MDR, and we observed no acquisition of resistance for one month. This accelerated germicidal mechanism was attributed to multitargeting with lipopolysaccharides, phosphoethanolamine, phosphatidylglycerol, and cardiolipin, and the synergetic interactions induced a high curvature of the bacterial membrane, which facilitated simultaneously efficient damage to both inner and outer membrane. The LP-20 effectively prolonged the lifetime of myositis mice with Escherichia coli MDR and pneumonia mice with Klebsiella pneumoniae through a hepatic metabolism with ignorable toxicity. This study provides critical information for the fabrication of lipopeptide-based nano-antibiotics for the efficient control of intractable MDR caused by Gram-negative pathogens.
Keywords: antibacterial resistance; bacterial pneumonia; lipopeptides; membrane curvature; self-assembly.