title: Bacterial swimmers that infiltrate and take over the biofilm matrix.
abstract: Bacteria grow in either planktonic form or as biofilms, which are attached to either inert or biological surfaces. Both growth forms are highly relevant states in nature and of paramount scientific focus. However, interchanges between bacteria in these two states have been little explored. We discovered that a subpopulation of planktonic bacilli is propelled by flagella to tunnel deep within a biofilm structure. Swimmers create transient pores that increase macromolecular transfer within the biofilm. Irrigation of the biofilm by swimmer bacteria may improve biofilm bacterial fitness by increasing nutrient flow in the matrix. However, we show that the opposite may also occur (i.e., swimmers can exacerbate killing of biofilm bacteria by facilitating penetration of toxic substances from the environment). We combined these observations with the fact that numerous bacteria produce antimicrobial substances in nature. We hypothesized and proved that motile bacilli expressing a bactericide can also kill a heterologous biofilm population, Staphylococcus aureus in this case, and then occupy the newly created space. These findings identify microbial motility as a determinant of the biofilm landscape and add motility to the complement of traits contributing to rapid alterations in biofilm populations.
authors: Institut National de la Recherche Agronomique, Micalis Institute, UMR1319, F-78350 Jouy-en-Josas, France.
authors: Ali
authors: A
authors: Houry
authors: Michel
authors: M
authors: Gohar
authors: Julien
authors: J
authors: Deschamps
authors: Ekaterina
authors: E
authors: Tischenko
authors: Stéphane
authors: S
authors: Aymerich
authors: Alexandra
authors: A
authors: Gruss
authors: Romain
authors: R
authors: Briandet
mesh_terms: D001413:Bacillus thuringiensis / Q000378:metabolism / Q000502:physiology*; D018441:Biofilms / Q000254:growth & development*; D005109:Extracellular Matrix / Q000378:metabolism*; D016650:Fluorescein-5-isothiocyanate; D049452:Green Fluorescent Proteins; D007700:Kinetics; D008124:Locomotion / Q000502:physiology*; D008248:Lysostaphin / Q000378:metabolism; D056265:Microbial Interactions / Q000502:physiology*; D008856:Microscopy, Fluorescence; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000187:drug effects; D013997:Time Factors; D059008:Time-Lapse Imaging
chemical_list: D049452:Green Fluorescent Proteins; D008248:Lysostaphin; D016650:Fluorescein-5-isothiocyanate