Lynronne antimicrobial peptides with terminal D amino acid enantiomers synergize with bedaquiline against Mycobacterium tuberculosis

Abstract Tuberculosis (TB) treatment is challenging due to prolonged chemotherapy and rising multidrug resistance. Here, we investigated the antimicrobial properties of the antimicrobial peptides (AMPs) lynronne (LYN)-1, -2 and -3, both in their natural form or with terminal D-enantiomers, alongside their synergistic effects with common TB drugs. Notably, D-enantiomer replacement improves LYNs’ stability and activity. Moreover, lynronne-1D (LYN1D) and lynronne-3D (LYN3D) is synergistic with bedaquiline (BDQ), significantly reducing the bactericidal concentrations of LYN1D, LYN3D and BDQ. Transcriptome studies demonstrated that this synergy is associated with perturbation of multiple pathways, including negative transcriptional regulators, lipid transporters, arabinogalactan biosynthesis, and the oxidative phosphorylation pathway. Furthermore, cellular morphology changes and ATP reduction suggested a synergistic model where the combination of LYNDs with BDQ simultaneously targets cell membrane lipids and energy production, resulting in the eradication of Mycobacterium tuberculosis. This synergistic combination of BDQ with D-enantiomers AMPs offers a novel TB treatment strategy, and a model for developing synergistic drug combinations to tackle other infectious diseases.