Murepavadin (POL7080) (TFA), a 14-amino-acid cyclic peptide, is a highly potent, specific antibiotic. Murepavadin exhibits a potent antimicrobial activity for P. aeruginosa with MIC50 and MIC90 values both of 0.12 mg/L. Murepavadin also can target the lipopolysaccharide transport portin D. Murepavadin can be used for the research of bacterial resistance.