Exploring in vitro efficacy of rCHAPk with antibiotic combinations, and promising findings of its therapeutic potential for clinical-originated MRSA wound infection


TAŞDURMAZLI S., Cinar I., Karamese M., Aksak Karamese S., ÇADIRCI E., Melo L. D., ...More

International Journal of Biological Macromolecules, vol.296, 2025 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 296
  • Publication Date: 2025
  • Doi Number: 10.1016/j.ijbiomac.2025.139630
  • Journal Name: International Journal of Biological Macromolecules
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, EMBASE, Food Science & Technology Abstracts, INSPEC, Veterinary Science Database
  • Keywords: Endolysin rCHAPk, Endolysin-antibiotic synergism, MRSA-infected in vivo wound model
  • Yıldız Technical University Affiliated: Yes

Abstract

The increasing threat of antimicrobial-resistant bacteria, particularly Staphylococcus aureus, which rapidly develops multidrug resistance and commonly colonizes wound surfaces, demands innovative strategies. Phage-encoded endolysins offer a dual-purpose approach as topical therapies for infectious skin wounds and synergistic agents to reduce high-dose antibiotic dependence. This study explores recombinant CHAPk (rCHAPk), efficiently synthesized within 3 h, displaying broad-spectrum antibacterial activity against 10 Gram-positive strains, including resistant variants, with rapid bactericidal kinetics. Application of 10 μg of rCHAPk reduced OD600 by 0.4 within 5 min against a clinical methicillin-resistant S. aureus (MRSA) strain. Combining rCHAPk (1.875 μg/mL) with oxacillin/vancomycin lowered their minimum bactericidal concentrations to 1 μg/mL from initial values over 64 μg/mL and 32 μg/mL, respectively, with a fractional inhibitory concentration index below 0.1. rCHAPk retained efficacy after one year of refrigerated storage. In in vivo experiments, rCHAPk outperformed commercial fucidin therapy in MRSA-induced murine wound models over two weeks, enhancing wound healing by modulating pro-inflammatory cytokine responses and the proliferative phase. This study, for the first time, investigates rCHAPk's in vitro combination with antibiotics and wound healing parameters, highlighting its potential as a potent antibacterial agent synergizing with antibiotics to address antibiotic-resistant bacterial wound infections.