Single dose eradication of extensively drug resistant Acinetobacter spp. In a mouse model of burn infection by melittin antimicrobial peptide.

Bacterial infections caused by antibiotic resistant bacteria are the leading cause of morbidity and mortality after burn injuries. This issue has driven the need for promising antimicrobial drugs to eradication of bacterial pathogens. Accordingly, we aimed to determine the therapeutic value of melittin, as a natural Antimicrobial peptide (AMP), in eradication of extensively drug-resistant (XDR) Acinetobacter spp. on a mouse model of third degree burn infection. Melittin killed all examined XDR isolates at 4 μg/mL up to 3 h. Melittin caused significant fluorescence release from XDR isolates at the minimum dose of 0.062 μg/mL. Vesicle formation on the membrane and squeezing of bacteria followed by cell lysis indicated the membranolytic effect of melittin. Melittin at 32 μg/mL completely eradicated the colonized XDR bacteria on infected burn mice during 2 h. No toxicity was observed on injured or healthy derma, as well as circulating Red Blood Cells (RBCs) in the examined mice. Potent promising antibacterial activity of melittin and the lack of toxicity at the therapeutic dose can clarify that melittin can be implemented as a topical drug lead in a preclinical trial of third degree burn infections.