Peptide-Based Conjugate Makes Erythromycin Work Against Gram-Negative Bacteria Again

The niacin-cholic acid-peptide conjugate (amphiphile 1) acts as a membrane disruptor for Gram-negative bacteria, creating entry points for erythromycin. The combination was bactericidal against Gram-negative pathogens, eliminated monomicrobial and polymicrobial biofilms, and showed antibacterial effectiveness in wound infection models. This approach repurposes an existing antibiotic for infections it normally cannot treat.

Peptide conjugate design and synthesis, followed by in vitro testing against Gram-negative bacteria. Assessed membrane disruption, bactericidal activity, and biofilm elimination. Tested in monomicrobial and polymicrobial wound infection models.

Antibiotic resistance, especially in Gram-negative bacteria, is a global health crisis. Rather than developing entirely new antibiotics, this approach uses a peptide conjugate to make existing antibiotics work against bacteria they couldn't previously kill — a faster and cheaper path to new treatments.

Peptide-drug conjugates represent a growing strategy for combating antibiotic resistance. By using peptides to disrupt bacterial membranes, previously ineffective antibiotics can be revitalized — potentially extending the useful life of our existing antibiotic arsenal.

Primarily in vitro and wound model data — no systemic in vivo pharmacokinetics or toxicity data. Unclear whether the conjugate would be stable and effective in human wound environments. Only tested with erythromycin; other antibiotic combinations not explored. Long-term resistance development not assessed.