Walnut glutelin antibacterial peptides target Staphylococcus aureus through metabolic pathway and novel antibacterial...

To address challenges from biofilm-forming, antibiotic-resistant pathogens like Staphylococcus aureus, this study explored walnut glutelin antibacterial peptides (WGAP) as sustainable alternatives, integrating metabolomics, peptidomics, and computational biology to uncover their mechanisms and identify novel antibacterial peptides. WGAP exhibited significant efficacy against Staphylococcus aureus (MIC = 53.5 μg/mL) with minimal hemolysis (<8.53% at 8 × MIC). WGAP treatment reduced bacterial surface hydrophobicity by 80%, thereby reducing bacterial adhesion to abiotic surfaces and subsequent biofilm formation. Metabolomics revealed that WGAP impaired nicotinamide cofactor synthesis, purine metabolism, and TCA cycle intermediates, thereby undermining energy homeostasis. Furthermore, effective antibacterial components of WGAP were isolated using inhibition zone analysis, ultrafiltration, and chromatography, and peptidomics identified five novel peptides. Molecular docking revealed strong binding of WGAP peptides-especially DVLINAYR and APQLLYIVK-to Staphylococcus aureus endonuclease-IV via hydrogen bonds and hydrophobic interactions at catalytic sites, highlighting WGAP'S antibacterial action and its potential as a sustainable, plant-based solution against food spoilage and antibiotic resistance.