Algerian honeybee venom antioxidant and antimicrobial activities: molecular docking of melittin as a dual inhibitor of PBP2a and Keap1
Honeybee venom is a complex bioactive secretion dominated by melittin, with recognized antioxidant and antimicrobial therapeutic potential. This study characterized Algerian honeybee venom (AHBV) through biochemical profiling, in vitro antioxidant and antimicrobial assays, and in silico molecular docking to explore melittin’s dual targeting capacity. AHBV was characterized using size-exclusion fast protein liquid chromatography, Fourier-transform infrared spectroscopy, the Bradford assay, the ABTS radical-scavenging assay, antimicrobial evaluation, and molecular docking of melittin against PBP2a and Keap1 using pyDock. Size-exclusion fast protein liquid chromatography revealed a protein profile dominated by low-molecular-weight peptides (<5 kDa), with only minor higher-molecular-weight components, consistent with the known composition of Apis mellifera venom. Fourier-transform infrared spectroscopy confirmed the proteinaceous, peptide-rich nature of the venom through characteristic amide I and II bands. Total protein content, determined by the Bradford assay, was 204.8 ± 16.26 μg BSA equivalents/mL. AHBV exhibited marked antioxidant activity in the ABTS radical-scavenging assay (727.0 ± 4.9 μmol Trolox equivalents/mg). Antimicrobial evaluation demonstrated significant activity against Gram-positive bacteria, particularly Staphylococcus aureus (MIC 15.62–62.5 μg/mL), moderate efficacy against Gram-negative strains (MIC 125–500 μg/mL), and measurable antifungal activity against Candida albicans (MIC 250 μg/mL). Molecular docking of melittin against PBP2a and Keap1 revealed a potential dual targeting: melittin is predicted to bind the PBP2a allosteric pocket with a pyDock score of −40.406 kcal/mol, and potentially engage the Keap1 Kelch domain (−31.537 kcal/mol) through hydrophobic contacts critical for Nrf2 recognition. This interaction suggests a mechanism for resensitizing MRSA to β-lactam antibiotics, indicating a possible role in activating the antioxidant response pathway. Taken together, these findings provide region-specific data on Algerian honeybee venom and position melittin as a promising bifunctional therapeutic candidate against antimicrobial resistance and oxidative stress-related disorders.