Liquid Crystal Emulsions That Intercept and Report on Bacterial Quorum Sensing

• DOI: 10.1021/acsami.0c05792
• Publication Date: 2020-06-02T20:53:31Z
• Authors: Benjamín J. Ortiz; Michelle E. Boursier; Kelsey L. Barrett; Daniel E. Manson; Daniel Amador-Noguez; Nicholas L. Abbott; Helen E. Blackwell; David M. Lynn
• Keywords: Rhamnolipid; Pyocyanin; Virulence factor; Bacterial growth; Autoinducer

We report aqueous emulsions of thermotropic liquid crystals (LCs) that can intercept and on the presence N-acyl-l-homoserine lactones (AHLs), a class amphiphiles used by pathogenic bacteria to regulate quorum sensing (QS), monitor population densities, initiate group activities, including biofilm formation virulence factor production. The concentration AHL required promote "bipolar" "radial" transitions in micrometer-scale droplets nematic LC 4′-pentyl-cyanobiphenyl (5CB) decreases with increasing carbon number acyl tail, reaching threshold 7.1 μM for 3-oxo-C12-AHL, native QS signal pathogen Pseudomonas aeruginosa. these also respond biologically relevant concentrations biosurfactant rhamnolipid, produced communities P. aeruginosa under control QS. Systematic studies using bacterial mutants support conclusion selectively production rhamnolipid AHLs not other products at lower (subquorate) densities. Finally, remain configurationally stable growth media, enabling them be deployed either supernatants or situ cultures eavesdrop changes behavior detected real time polarized light. Our results provide new tools detect materials platform rapid monitoring communication resulting behaviors communities.