Dual-Mechanism Peptide SR25 has Broad Antimicrobial Activity and Potential Application for Healing Bacteria-infected Diabetic Wounds

Adv Sci (Weinh). 2024 Aug;11(30):e2401793. doi: 10.1002/advs.202401793. Epub 2024 Jun 14.

Abstract

The rise of antibiotic resistance poses a significant public health crisis, particularly due to limited antimicrobial options for the treatment of infections with Gram-negative pathogens. Here, an antimicrobial peptide (AMP) SR25 is characterized, which effectively kills both Gram-negative and Gram-positive bacteria through a unique dual-targeting mechanism without detectable resistance. Meanwhile, an SR25-functionalized hydrogel is developed for the efficient treatment of infected diabetic wounds. SR25 is obtained through genome mining from an uncultured bovine enteric actinomycete named Nonomuraea Jilinensis sp. nov. Investigations reveal that SR25 has two independent cellular targets, disrupting bacterial membrane integrity and restraining the activity of succinate:quinone oxidoreductase (SQR). In a diabetic mice wound infection model, the SR25-incorporated hydrogel exhibits high efficacy against mixed infections of Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA), accelerating wound healing. Overall, these findings demonstrate the therapeutic potential of SR25 and highlight the value of mining drugs with multiple mechanisms from uncultured animal commensals for combating challenging bacterial pathogens.

Keywords: antimicrobial peptides; diabetic wound; hydrogel; membrane disrupting; succinate:quinone reductase; uncultured bacteria.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Antimicrobial Peptides / pharmacology
  • Diabetes Mellitus, Experimental* / drug therapy
  • Disease Models, Animal*
  • Escherichia coli / drug effects
  • Methicillin-Resistant Staphylococcus aureus / drug effects
  • Mice
  • Microbial Sensitivity Tests
  • Wound Healing* / drug effects
  • Wound Infection / drug therapy
  • Wound Infection / microbiology

Substances

  • Antimicrobial Peptides
  • Anti-Bacterial Agents