Host metabolites stimulate the bacterial proton motive force to enhance the activity of aminoglycoside antibiotics

• DOI: 10.1371/journal.ppat.1007697
• Publication Date: 2019-04-29T22:55:43Z
• Authors: Aurélie Crabbé; Lisa Ostyn; Sorien Staelens; Charlotte Rigauts; Martijn Risseeuw; Maarten Dhaenens; Simon Daled; Heleen Van Acker; Dieter Deforce; Serge Van Calenbergh; Tom Coenye
• Keywords: 0301 basic medicine; QH301-705.5; Immunology; Microbial Sensitivity Tests; Microbiology; 03 medical and health sciences; Virology; Medicine and Health Sciences; Genetics; Humans; Pseudomonas Infections; Biology (General); Molecular Biology; Lung; Cells, Cultured; Proton-Motive Force; Epithelial Cells; RC581-607; Anti-Bacterial Agents; 3. Good health; Biofilms; Culture Media, Conditioned; Pseudomonas aeruginosa; Metabolome; Tobramycin; Parasitology; Immunologic diseases. Allergy; Research Article

Antibiotic susceptibility of bacterial pathogens is typically evaluated using in vitro assays that do not consider the complex host microenvironment. This may help explaining a significant discrepancy between antibiotic efficacy and vivo, with some antibiotics being effective but vivo or vice versa. Nevertheless, it well-known bacteria driven by environmental factors. Lung epithelial cells enhance activity aminoglycoside against opportunistic pathogen Pseudomonas aeruginosa, yet mechanism behind unknown. The present study addresses this gap provides mechanistic understanding on how lung stimulate activity. To investigate influence local microenvironment activity, an vivo-like three-dimensional (3-D) cell model was used. We report conditioned medium 3-D cells, containing secreted cellular components, potentiated bactericidal aminoglycosides P. including resistant clinical isolates, several other pathogens. In contrast, obtained from same type, grown as conventional (2-D) monolayers did efficacy. found endogenous metabolites (including succinate glutamate) enhanced provide evidence pyruvate metabolism linked to observed potentiation antimicrobial Biochemical phenotypic indicated stimulated proton motive force (PMF), resulting increased intracellular pH. latter uptake, determined fluorescently labelled tobramycin combination flow cytometry analysis. Our findings reveal cross-talk metabolic pathways, downstream antibiotics. Understanding underlying basis lead improved diagnostic approaches pave way towards novel means