Pseudomonas aeruginosa detachment from surfaces via a self-made small molecule.

TitlePseudomonas aeruginosa detachment from surfaces via a self-made small molecule.
Publication TypeJournal Article
Year of Publication2021
AuthorsScheffler, RJ, Sugimoto, Y, Bratton, BP, Ellison, CK, Koch, MD, Donia, MS, Gitai, Z
JournalJ Biol Chem
Date Published2021 Jan-Jun
KeywordsAniline Compounds, Biofilms, Fimbriae, Bacterial, Gene Expression Regulation, Bacterial, Humans, Hydroxyquinolines, Pseudomonas aeruginosa, Pseudomonas Infections, Quinolones, Single-Cell Analysis, Virulence

<p>Pseudomonas aeruginosa is a significant threat in both healthcare and industrial biofouling. Surface attachment of P. aeruginosa is particularly problematic as surface association induces virulence and is necessary for the ensuing process of biofilm formation, which hampers antibiotic treatments. Previous efforts have searched for dispersal agents of mature biofilm collectives, but there are no known factors that specifically disperse individual surface-attached P. aeruginosa. In this study, we develop a quantitative single-cell surface-dispersal assay and use it to show that P. aeruginosa itself produces factors that can stimulate its dispersal. Through bioactivity-guided fractionation, mass spectrometry, and nuclear magnetic resonance, we elucidated the structure of one such factor, 2-methyl-4-hydroxyquinoline (MHQ). MHQ is an alkyl quinolone with a previously unknown activity and is synthesized by the PqsABC enzymes. Pure MHQ is sufficient to disperse P. aeruginosa, but the dispersal activity of natural P. aeruginosa conditioned media requires additional factors. Whereas other alkyl quinolones have been shown to act as antibiotics or membrane depolarizers, MHQ lacks these activities and known antibiotics do not induce dispersal. In contrast, we show that MHQ inhibits the activity of Type IV Pili (TFP) and that TFP targeting can explain its dispersal activity. Our work thus identifies single-cell surface dispersal as a new activity of P. aeruginosa-produced small molecules, characterizes MHQ as a promising dispersal agent, and establishes TFP inhibition as a viable mechanism for P. aeruginosa dispersal.</p>

Alternate JournalJ Biol Chem
PubMed ID33450229
PubMed Central IDPMC7949062
Grant ListDP1 AI124669 / AI / NIAID NIH HHS / United States
DP2 AI124441 / AI / NIAID NIH HHS / United States
T32 GM007388 / GM / NIGMS NIH HHS / United States