WLBU2 acetate is an engineered cationic antimicrobial peptide (eCAP) designed to overcome the sensitivity issues of natural antimicrobial peptides (AMPs) in various environments. It exhibits rapid bactericidal activity with minimum inhibitory concentrations (MIC) of ≤10 μM against numerous Gram-positive and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Klebsiella pneumoniae, Enterobacter aerogenes, Enterobacter cloacae, and Escherichia coli. WLBU2 acetate effectively inhibits biofilm growth of Pseudomonas aeruginosa and remains active in conditions rich in mucus, low pH, and high salt concentrations, without adverse effects on human respiratory epithelial cells. This compound is applicable for research related to cystic fibrosis (CF) and Pseudomonas aeruginosa infections.