Antimicrobial activity of synthetic cationic peptides and lipopeptides derived from human lactoferricin against Pseudomonas aeruginosa planktonic cultures and biofilms.

Synthetic peptides derived from human lactoferricin demonstrated potent bactericidal activity against Pseudomonas aeruginosa planktonic cells and biofilms. Acylation enhanced killing of planktonic bacteria but reduced anti-biofilm activity. Peptides LF11-215 and LF11-227 caused a 10,000-fold reduction in biofilm viability at 10x MIC with low cytotoxicity, and LF11-227 removed over 50% of biofilm mass.

The study used microdilution assays to determine MIC and MBC against planktonic bacteria, time-kill studies to assess killing speed, and biofilm assays under static and dynamic flow conditions to evaluate anti-biofilm activity. Both non-acylated peptides and N-acylated lipopeptides were tested.

Pseudomonas aeruginosa biofilms are highly resistant to antibiotics, posing treatment challenges. These peptides offer a new approach to effectively kill both free bacteria and biofilms, potentially improving infection control.

The study did not specify clinical trial data or in vivo testing, and further optimization of peptide structure is needed to enhance anti-biofilm activity.