Modular Engineering of Lysostaphin with Significantly Improved Stability and Bioavailability for Treating MRSA Infections

Methicillin-resistant Staphylococcus aureus (MRSA) is a refractory pneumonia-causing pathogen due to the antibiotic resistance and the characteristics of persisting inside its host cell. Lysostaphin is a typical bacteriolytic enzyme for degrading bacterial cell walls via hydrolysis of pentaglycine cross-links, showing potential to combat multidrug-resistant bacteria. However, there are still grand challenges for native lysostaphin because of its poor shelf stability and limited bioavailability. To tackle these limitations, a modular assembly strategy is proposed to actively engineer the native lysostaphin, involving nanoassembly preparation via fusing with lysine-rich polypeptide. The engineered lysine component significantly improves the membrane-penetration capability of lysostaphin, greatly increasing its intracellular antibacterial activity by 12-fold compared to wild-type lysostaphin. Notably, the half-life of the nanoassembled lysostaphin is approximately 13 times longer than that of its native counterpart, greatly outperforming other studies. Most importantly, the shelf stability of our engineered lysostaphin is significantly improved, retaining over 99.9% of antibacterial activity after 12 weeks at room temperature. This modular assembly strategy successfully enhances the overall performance of lysostaphin, offering great promise for a platform technique to refine enzymatic material for widespread clinical demands.