Given the ability of Staphylococcus aureus to form biofilms and produce persister cells, making infections difficult to treat with antibiotics alone, there is a pressing need for an effective antibiotic adjuvant to address this public health threat. In this study, a series of quinone derivatives were evaluated for their antimicrobial and antibiofilm activities against methicillin-susceptible and methicillin-resistant S. aureus reference strains. Following analyses using broth microdilution, growth curve analysis, checkerboard assay, time-kill experiments, and confocal laser scanning microscopy, menadione was identified as a hit compound. Menadione exhibited a notable antibacterial profile (minimum inhibitory concentration, MIC = 4-16 μg/ml; minimum bactericidal concentration, MBC = 256 μg/ml) against planktonic S. aureus and its biofilms (minimum biofilm inhibitory concentration, MBIC 50 = 0.0625-0.25 μg/ml). When combined with oxacillin, erythromycin, and vancomycin, menadione exhibited a synergistic or additive effect against planktonic cells and biofilms of two S. aureus reference strains and six clinical isolates, highlighting its potential as a suitable adjuvant for further development against S. aureus biofilm-associated infections.
Keyphrases
- staphylococcus aureus
- candida albicans
- methicillin resistant staphylococcus aureus
- biofilm formation
- induced apoptosis
- public health
- cell cycle arrest
- early stage
- escherichia coli
- high resolution
- optical coherence tomography
- cancer therapy
- endoplasmic reticulum stress
- pseudomonas aeruginosa
- cell death
- single molecule
- oxidative stress
- cell proliferation
- signaling pathway
- mass spectrometry
- drug delivery