title: Impact of environmental and genetic factors on biofilm formation by the probiotic strain Lactobacillus rhamnosus GG.
abstract: Lactobacillus rhamnosus GG (ATCC 53103) is one of the clinically best-studied probiotic organisms. Moreover, L. rhamnosus GG displays very good in vitro adherence to epithelial cells and mucus. Here, we report that L. rhamnosus GG is able to form biofilms on abiotic surfaces, in contrast to other strains of the Lactobacillus casei group tested under the same conditions. Microtiter plate biofilm assays indicated that in vitro biofilm formation by L. rhamnosus GG is strongly modulated by culture medium factors and conditions related to the gastrointestinal environment, including low pH; high osmolarity; and the presence of bile, mucins, and nondigestible polysaccharides. Additionally, phenotypic analysis of mutants affected in exopolysaccharides (wzb), lipoteichoic acid (dltD), and central metabolism (luxS) showed their relative importance in biofilm formation by L. rhamnosus GG.
authors.affiliation: Centre of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, 3001 Leuven, Belgium.
authors.forename: Sarah
authors.initials: S
authors.lastname: Lebeer
authors.forename: Tine L A
authors.initials: TL
authors.lastname: Verhoeven
authors.forename: Mónica
authors.initials: M
authors.lastname: Perea Vélez
authors.forename: Jos
authors.initials: J
authors.lastname: Vanderleyden
authors.forename: Sigrid C J
authors.initials: SC
authors.lastname: De Keersmaecker
mesh_terms: D001422:Bacterial Adhesion / Q000502:physiology*; D001426:Bacterial Proteins / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development*; D013437:Carbon-Sulfur Lyases / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D052201:Lacticaseibacillus rhamnosus / Q000235:genetics* / Q000502:physiology; D008070:Lipopolysaccharides / Q000378:metabolism; D011135:Polysaccharides, Bacterial / Q000378:metabolism; D019936:Probiotics; D013682:Teichoic Acids / Q000378:metabolism