title: Cell morphology drives spatial patterning in microbial communities.
abstract: The clearest phenotypic characteristic of microbial cells is their shape, but we do not understand how cell shape affects the dense communities, known as biofilms, where many microbes live. Here, we use individual-based modeling to systematically vary cell shape and study its impact in simulated communities. We compete cells with different cell morphologies under a range of conditions and ask how shape affects the patterning and evolutionary fitness of cells within a community. Our models predict that cell shape will strongly influence the fate of a cell lineage: we describe a mechanism through which coccal (round) cells rise to the upper surface of a community, leading to a strong spatial structuring that can be critical for fitness. We test our predictions experimentally using strains of Escherichia coli that grow at a similar rate but differ in cell shape due to single amino acid changes in the actin homolog MreB. As predicted by our model, cell types strongly sort by shape, with round cells at the top of the colony and rod cells dominating the basal surface and edges. Our work suggests that cell morphology has a strong impact within microbial communities and may offer new ways to engineer the structure of synthetic communities.
authors.affiliation: Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom.
authors.forename: William P J
authors.initials: WP
authors.lastname: Smith
authors.affiliation: Institut de Mécanique des Fluides de Toulouse (IMFT), Université de Toulouse, Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique de Toulouse (INPT), Université Paul Sabatier (UPS), F-31400 Toulouse, France.
authors.forename: Yohan
authors.initials: Y
authors.lastname: Davit
authors.affiliation: School of Mathematics and Statistics, University of Melbourne, VIC 3010, Australia.
authors.forename: James M
authors.initials: JM
authors.lastname: Osborne
authors.affiliation: Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom.
authors.forename: Wook
authors.initials: W
authors.lastname: Kim
authors.affiliation: Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom kevin.foster@zoo.ox.ac.uk joe.pitt-francis@cs.ox.ac.uk.
authors.forename: Kevin R
authors.identifier: 0000-0003-4687-6633
authors.initials: KR
authors.lastname: Foster
authors.affiliation: Department of Computer Science, University of Oxford, Oxford OX1 3QD, United Kingdom; kevin.foster@zoo.ox.ac.uk joe.pitt-francis@cs.ox.ac.uk.
authors.forename: Joe M
authors.initials: JM
authors.lastname: Pitt-Francis
mesh_terms: D057005:Bioengineering; D018441:Biofilms; D055592:Biophysical Phenomena; D003198:Computer Simulation; D004926:Escherichia coli / Q000166:cytology* / Q000235:genetics / Q000254:growth & development; D029968:Escherichia coli Proteins / Q000235:genetics; D059013:Microbial Consortia / Q000235:genetics / Q000502:physiology; D008954:Models, Biological; D009154:Mutation; D010641:Phenotype; D058615:Synthetic Biology
chemical_list: D029968:Escherichia coli Proteins; C078473:MreB protein, E coli
keywords: biofilms; biophysics; cell morphology; self-organization; synthetic biology