Rational Design of Novel Anti-Staphylococcal Peptides Using Machine Learning-Guided QSAR Modeling and Experimental Validation
摘要
The global health crisis of antibiotic-resistant infections, particularly in chronic wounds, demands innovative therapeutic strategies. Antimicrobial peptides (AMPs) represent promising candidates due to their low resistance potential and multi-target mechanisms.
MethodsWe developed an interpretable machine learning-guided QSAR model using a random forest (RF) algorithm based on 2D molecular descriptors to predict the minimum inhibitory concentration (MIC) of AMPs against Staphylococcus aureus. The dataset was curated from the DBAASP database and filtered based on MIC thresholds, peptide length (5–15 amino acids), and culture conditions. External validation yielded (R²test = 0.84, Q²F1 = 0.61, MAE = 0.18).
ResultsFeature importance analysis revealed three key descriptors: maxHBint2 (hydrogen bonding capacity), SpMin7_Bhe, and SpMin6_Bhp (Burden eigenvalues reflecting molecular topology). Using this model, we designed and synthesized two novel pentapeptides, R2W3 and R2W2L, which exhibited potent anti-staphylococcal activity (MIC = 41.68 and 24.54 µM, respectively). In vitro assays confirmed low cytotoxicity (< 10%) and < 5% hemolysis. Molecular docking revealed distinct target specificities: R2W3 showed strong binding to dihydrofolate reductase type 1 (ΔG = -16.84 kcal/mol), while R2W2L preferentially interacted with DNA gyrase subunit B (ΔG = -8.39 kcal/mol).
ConclusionsOur study establishes a robust computational-experimental pipeline for designing anti-Staphylococcal peptides with validated safety and efficacy. This approach provides a foundation for integrating multi-endpoint prediction and next-generation AMP discovery strategies.