Eying up predatory bacteria: living antimicrobials for ocular infections

Purpose of review The growing threat of antibiotic-resistant pathogens, particularly in ocular infections like bacterial keratitis, necessitates alternative therapeutic strategies. This review evaluates the potential therapeutic role of predatory bacteria as novel live antimicrobials, offering a timely exploration of their potential in overcoming resistance mechanisms such as biofilm formation and persister cell development. Recent findings Predatory bacteria, including Bdellovibrio bacterovorus and Micavibrio aerguinosavorus selectively target Gram-negative bacteria, including Pseudomonas aeruginosa , while sparing Gram-positive ocular surface. They exhibit rapid bactericidal activity and efficacy against biofilms, persister cells, and antibiotic-resistant pathogens, but induce little inflammation. Advances in storage and delivery methods, such as lyophilization, cryomicroneedles, and thermoresponsive hydrogels, have potential to increase their therapeutic feasibility. However, in-vivo efficacy remains variable and their narrow spectrum limits effectiveness against Gram-positive pathogens. Summary Predatory bacteria present a promising alternative to traditional antibiotics in ocular therapeutics, particularly for drug-resistant infections. Integration of predatory bacteria with bacteriophages or conventional antibiotics may further optimize their potential. Continued translational research is essential to address current limitation and to validate their safety and efficacy for human or veterinary applications.