title: Inhibition of Pseudomonas aeruginosa swarming motility by 1-naphthol and other bicyclic compounds bearing hydroxyl groups.
abstract: Many bacteria convert bicyclic compounds, such as indole and naphthalene, to oxidized compounds, including hydroxyindoles and naphthols. Pseudomonas aeruginosa, a ubiquitous bacterium that inhabits diverse environments, shows pathogenicity against animals, plants, and other microorganisms, and increasing evidence has shown that several bicyclic compounds alter the virulence-related phenotypes of P. aeruginosa. Here, we revealed that hydroxyindoles (4- and 5-hydroxyindoles) and naphthalene derivatives bearing hydroxyl groups specifically inhibit swarming motility but have minor effects on other motilities, including swimming and twitching, in P. aeruginosa. Further analyses using 1-naphthol showed that this effect is also associated with clinically isolated hyperswarming P. aeruginosa cells. Swarming motility is associated with the dispersion of cells from biofilms, and the addition of 1-naphthol maintained biofilm biomass without cell dispersion. We showed that this 1-naphthol-dependent swarming inhibition is independent of changes of rhamnolipid production and the intracellular level of signaling molecule cyclic-di-GMP (c-di-GMP). Transcriptome analyses revealed that 1-naphthol increases gene expression associated with multidrug efflux and represses gene expression associated with aerotaxis and with pyochelin, flagellar, and pilus synthesis. In the present study, we showed that several bicyclic compounds bearing hydroxyl groups inhibit the swarming motility of P. aeruginosa, and these results provide new insight into the chemical structures that inhibit the specific phenotypes of P. aeruginosa.
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Hiromu
authors: H
authors: Oura
authors: Department of Applied Chemistry and Biochemical Engineering, Graduate School of Engineering, Shizuoka University, Hamamatsu, Shizuoka, Japan.
authors: Yosuke
authors: Y
authors: Tashiro
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Masanori
authors: M
authors: Toyofuku
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Kousetsu
authors: K
authors: Ueda
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Tatsunori
authors: T
authors: Kiyokawa
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Satoshi
authors: S
authors: Ito
authors: Biotechnology Research Center, The University of Tokyo, Tokyo, Japan.
authors: Yurika
authors: Y
authors: Takahashi
authors: Biotechnology Research Center, The University of Tokyo, Tokyo, Japan.
authors: Seunguk
authors: S
authors: Lee
authors: Biotechnology Research Center, The University of Tokyo, Tokyo, Japan.
authors: Hideaki
authors: H
authors: Nojiri
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Toshiaki
authors: T
authors: Nakajima-Kambe
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
authors: Hiroo
authors: H
authors: Uchiyama
authors: Department of Applied Chemistry and Biochemical Engineering, Graduate School of Engineering, Shizuoka University, Hamamatsu, Shizuoka, Japan.
authors: Hiroyuki
authors: H
authors: Futamata
authors: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan nomura.nobuhiko.ge@u.tsukuba.ac.jp.
authors: Nobuhiko
authors: N
authors: Nomura
mesh_terms: D020869:Gene Expression Profiling; D017665:Hydroxyl Radical; D007211:Indoles / Q000633:toxicity*; D008969:Molecular Sequence Data; D009281:Naphthalenes / Q000633:toxicity*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D017422:Sequence Analysis, DNA; D015398:Signal Transduction
chemical_list: D007211:Indoles; D009281:Naphthalenes; D017665:Hydroxyl Radical