Engineered Mycoplasma pneumoniae targeting dual-species bacterial biofilms: a novel strategy against infections.

Antimicrobial resistance is a major global health threat, potentially causing 8.22 million deaths annually by 2050. Polymicrobial biofilms significantly contribute to this crisis, leading to treatment failure, especially in chronic airway infections caused by Staphylococcus aureus and Pseudomonas aeruginosa, common in ventilator-associated pneumonia and cystic fibrosis. To address this, we engineered an attenuated Mycoplasma pneumoniae strain, CV8_HAD, to secrete biofilm-disrupting enzymes (PelAh, PslGh, A1-II' and Dispersin B). CV8_HAD showed strong in vitro activity against single and mixed-species biofilms of S. aureus and P. aeruginosa, and demonstrated in vivo efficacy against S. aureus biofilms in mice and mixed infections in Galleria mellonella larvae. This study establishes engineered M. pneumoniae as a promising therapeutic strategy for tackling microbial biofilms and highlights the potential of G. mellonella larvae models as an alternative to mouse models in advancing research on biofilm-targeting interventions.