title: Biofilm formation by a Bacillus subtilis strain that produces gamma-polyglutamate.
abstract: The extracellular matrix produced by Bacillus subtilis B-1, an environmental strain that forms robust floating biofilms, was purified, and determined to be composed predominantly of gamma-polyglutamate (gamma-PGA), with a molecular mass of over 1,000 kDa. Both biofilm formation and gamma-PGA production by B. subtilis B-1 increased with increasing Mn(2+) or glycerol concentration. gamma-PGA was produced in a growth-associated manner in standing culture, and floating biofilms were formed. However, gamma-PGA was produced in a non-growth-associated manner in shaking culture conditions. When B. subtilis B-1 was grown in a microaerated culture system, floating biofilm formation and gamma-PGA production were significantly retarded, suggesting that oxygen depletion is involved in the initial steps of floating biofilm formation in standing culture. Proteomic analysis of membrane proteins demonstrated that flagellin, oligopeptide permease and Vpr protease precursor were the major proteins produced by cells in a floating biofilm and a colony.
authors.affiliation: Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA.|Department of Material and Life Science, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Morikawa
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Kagihiro
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Haruki
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Takano
authors.affiliation: Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Steve
authors.initials: S
authors.lastname: Branda
authors.affiliation: Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Roberto
authors.initials: R
authors.lastname: Kolter
authors.affiliation: Department of Material and Life Science, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
authors.forename: Shigenori
authors.initials: S
authors.lastname: Kanaya
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology; D003470:Culture Media; D004305:Dose-Response Relationship, Drug; D005109:Extracellular Matrix / Q000737:chemistry / Q000648:ultrastructure; D005990:Glycerol / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008565:Membrane Proteins / Q000032:analysis; D008970:Molecular Weight; D010100:Oxygen / Q000378:metabolism; D010933:Plankton / Q000737:chemistry / Q000166:cytology; D011099:Polyglutamic Acid / Q000096:biosynthesis*; D020543:Proteome / Q000032:analysis; D040901:Proteomics
chemical_list: D003470:Culture Media; D008565:Membrane Proteins; D020543:Proteome; D011099:Polyglutamic Acid; D008345:Manganese; D005990:Glycerol; D010100:Oxygen