title: A self-produced trigger for biofilm disassembly that targets exopolysaccharide.
abstract: Biofilms are structured communities of bacteria that are held together by an extracellular matrix consisting of protein and exopolysaccharide. Biofilms often have a limited lifespan, disassembling as nutrients become exhausted and waste products accumulate. D-amino acids were previously identified as a self-produced factor that mediates biofilm disassembly by causing the release of the protein component of the matrix in Bacillus subtilis. Here we report that B. subtilis produces an additional biofilm-disassembly factor, norspermidine. Dynamic light scattering and scanning electron microscopy experiments indicated that norspermidine interacts directly and specifically with exopolysaccharide. D-amino acids and norspermidine acted together to break down existing biofilms and mutants blocked in the production of both factors formed long-lived biofilms. Norspermidine, but not closely related polyamines, prevented biofilm formation by B. subtilis, Escherichia coli, and Staphylococcus aureus.
authors.affiliation: Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
authors.forename: Ilana
authors.initials: I
authors.lastname: Kolodkin-Gal
authors.forename: Shugeng
authors.initials: S
authors.lastname: Cao
authors.forename: Liraz
authors.initials: L
authors.lastname: Chai
authors.forename: Thomas
authors.initials: T
authors.lastname: Böttcher
authors.forename: Roberto
authors.initials: R
authors.lastname: Kolter
authors.forename: Jon
authors.initials: J
authors.lastname: Clardy
authors.forename: Richard
authors.initials: R
authors.lastname: Losick
mesh_terms: D000596:Amino Acids / Q000096:biosynthesis / Q000378:metabolism; D001412:Bacillus subtilis / Q000235:genetics / Q000502:physiology*; D018441:Biofilms; D004926:Escherichia coli / Q000502:physiology; D009154:Mutation; D011073:Polyamines / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D013095:Spermidine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D013211:Staphylococcus aureus / Q000502:physiology
chemical_list: D000596:Amino Acids; D011073:Polyamines; D011135:Polysaccharides, Bacterial; C085953:exopolysaccharide, Bacillus; C006760:norspermidine; D013095:Spermidine