Endolysins for precision antimicrobial therapy and rapid bacterial detection: translational challenges and future directions

Antimicrobial resistance (AMR) represents a major global health challenge, necessitating the development of alternative therapeutic and diagnostic strategies. Among emerging approaches, bacteriophage-derived endolysins have attracted considerable attention as promising tools for combating bacterial infections. Endolysins are phage-encoded peptidoglycan-degrading enzymes that have shown significant potential for both antimicrobial and diagnostic applications against a wide range of bacterial pathogens. This review summarizes the current knowledge of endolysins, highlighting their rapid bacteriolytic activity, high target specificity, and diverse therapeutic and diagnostic applications. Beyond their antimicrobial potential, endolysin-derived cell wall-binding domains (CBDs) and phage receptor-binding proteins (RBPs) have emerged as highly specific recognition molecules for the rapid detection of bacterial pathogens in clinical diagnostics and food safety. Rapid and accurate pathogen detection is essential for timely disease management, infection control, and the prevention of foodborne contamination. Despite these promising attributes, several challenges continue to limit the clinical and industrial translation of endolysins, including constraints related to protein expression, stability, formulation, and large-scale production. Furthermore, the outer membrane of Gram-negative bacteria remains a major obstacle to endolysin activity by restricting access to the peptidoglycan layer. Recent advances in protein engineering, membrane-permeabilization strategies, and delivery approaches have provided promising solutions to overcome these limitations. Overall, this review provides a comprehensive overview of the current advances, translational challenges, and future prospects of engineered endolysins as precision antimicrobial agents and diagnostic tools for combating antimicrobial-resistant bacterial pathogens.