title: Dispersed cells represent a distinct stage in the transition from bacterial biofilm to planktonic lifestyles.
abstract: Bacteria assume distinct lifestyles during the planktonic and biofilm modes of growth. Increased levels of the intracellular messenger c-di-GMP determine the transition from planktonic to biofilm growth, while a reduction causes biofilm dispersal. It is generally assumed that cells dispersed from biofilms immediately go into the planktonic growth phase. Here we use single-nucleotide resolution transcriptomic analysis to show that the physiology of dispersed cells from Pseudomonas aeruginosa biofilms is highly different from those of planktonic and biofilm cells. In dispersed cells, the expression of the small regulatory RNAs RsmY and RsmZ is downregulated, whereas secretion genes are induced. Dispersed cells are highly virulent against macrophages and Caenorhabditis elegans compared with planktonic cells. In addition, they are highly sensitive towards iron stress, and the combination of a biofilm-dispersing agent, an iron chelator and tobramycin efficiently reduces the survival of the dispersed cells.
authors.affiliation: 1] Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore [2] NUS Graduate School of Integrative Sciences and Engineering, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Song Lin
authors.initials: SL
authors.lastname: Chua
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: 1] Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore [2] Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637551, Singapore.
authors.forename: Joey Kuok Hoong
authors.initials: JK
authors.lastname: Yam
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore.
authors.forename: Yicai
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Costerton Biofilm Center, Department of International Health, Immunology and Microbiology, University of Copenhagen, 2200 København N, Denmark.
authors.forename: Rebecca Munk
authors.initials: RM
authors.lastname: Vejborg
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore.
authors.forename: Bryan Giin Chyuan
authors.initials: BG
authors.lastname: Tan
authors.affiliation: 1] Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore [2] Center for Marine Bio-Innovation and School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia.
authors.forename: Staffan
authors.initials: S
authors.lastname: Kjelleberg
authors.affiliation: Costerton Biofilm Center, Department of International Health, Immunology and Microbiology, University of Copenhagen, 2200 København N, Denmark.
authors.forename: Tim
authors.initials: T
authors.lastname: Tolker-Nielsen
authors.affiliation: 1] Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore [2] Costerton Biofilm Center, Department of International Health, Immunology and Microbiology, University of Copenhagen, 2200 København N, Denmark.
authors.forename: Michael
authors.initials: M
authors.lastname: Givskov
authors.affiliation: 1] Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore 637551, Singapore [2] School of Biological Sciences, Nanyang Technological University, Singapore 639798, Singapore.
authors.forename: Liang
authors.initials: L
authors.lastname: Yang
mesh_terms: D000818:Animals; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development; D017173:Caenorhabditis elegans / Q000382:microbiology; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D007502:Iron Chelating Agents / Q000494:pharmacology; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D009154:Mutation; D009842:Oligopeptides / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D012329:RNA, Bacterial / Q000235:genetics; D059467:Transcriptome
chemical_list: D007502:Iron Chelating Agents; D009842:Oligopeptides; D012329:RNA, Bacterial; C062025:bis(3',5')-cyclic diguanylic acid; C042453:pyoverdin; D006152:Cyclic GMP