Aktywność antybiofilmowa peptydów pochodnych dermcydyny przeciwko patogenom Pseudomonas aeruginosa i Staphylococcus aureus

BACKGROUND: Pseudomonas aeruginosa and Staphylococcus aureus are major opportunistic pathogens capable of developing antibiotic resistance and forming device-associated biofilms, which complicate clinical management. The present study aimed to investigate the antimicrobial and anti-biofilm properties of dermcidin-derived peptides against clinical isolates of these bacteria. METHODS: Clinical isolates of methicillin-susceptible and methicillin-resistant S. aureus (MSSA and MRSA), as well as carbapenem-susceptible and carbapenem-resistant P. aeruginosa (CSPA and CRPA), were examined for their susceptibility to dermcidin-derived peptides (DCD-1 L, SSL-23, and SSL-25). The in vitro inhibitory activity of the peptides on bacterial adhesion and biofilm formation was evaluated at sub-MIC levels, while their biofilm-disrupting potential was assessed on mature biofilms. Furthermore, the expression of key biofilm-associated and quorum-sensing genes was quantified using qRT-PCR following peptide exposure. RESULTS: Dermcidin-derived peptides markedly inhibited bacterial attachment and biofilm formation at sub-inhibitory concentrations (1/2, 1/4, and 1/8 MIC). In addition, they exhibited strong biofilm eradication activity at higher concentrations (8×-64× MIC). Gene expression analysis revealed significant down-regulation of adhesion- and quorum-sensing-related genes in both S. aureus and P. aeruginosa after treatment. CONCLUSION: The results suggest that dermcidin-derived peptides, regardless of their net charge, possess potent inhibitory effects on bacterial attachment and biofilm development. These findings highlight their potential as promising therapeutic agents for the prevention and control of biofilm-associated infections.