title: Single-cell twitching chemotaxis in developing biofilms.
abstract: Bacteria form surface-attached communities, known as biofilms, which are central to bacterial biology and how they affect us. Although surface-attached bacteria often experience strong chemical gradients, it remains unclear whether single cells can effectively perform chemotaxis on surfaces. Here we use microfluidic chemical gradients and massively parallel automated tracking to study the behavior of the pathogen Pseudomonas aeruginosa during early biofilm development. We show that individual cells can efficiently move toward chemoattractants using pili-based "twitching" motility and the Chp chemosensory system. Moreover, we discovered the behavioral mechanism underlying this surface chemotaxis: Cells reverse direction more frequently when moving away from chemoattractant sources. These corrective maneuvers are triggered rapidly, typically before a wayward cell has ventured a fraction of a micron. Our work shows that single bacteria can direct their motion with submicron precision and reveals the hidden potential for chemotaxis within bacterial biofilms.
authors.affiliation: Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom; Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford OX1 3PS, United Kingdom.
authors.forename: Nuno M
authors.initials: NM
authors.lastname: Oliveira
authors.affiliation: Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom; Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford OX1 3PS, United Kingdom kevin.foster@zoo.ox.ac.uk william.durham@zoo.ox.ac.uk.
authors.forename: Kevin R
authors.identifier: 0000-0003-4687-6633
authors.initials: KR
authors.lastname: Foster
authors.affiliation: Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom; kevin.foster@zoo.ox.ac.uk william.durham@zoo.ox.ac.uk.
authors.forename: William M
authors.initials: WM
authors.lastname: Durham
mesh_terms: D018407:Bacterial Physiological Phenomena; D018441:Biofilms; D001681:Biological Assay; D002633:Chemotaxis; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D010861:Fimbriae, Bacterial / Q000502:physiology; D056656:Lab-On-A-Chip Devices; D011550:Pseudomonas aeruginosa / Q000502:physiology*
chemical_list: D004121:Dimethyl Sulfoxide
keywords: Pil-Chp system; Pseudomonas aeruginosa; Type IV pili; bacterial chemotaxis; twitching motility