title: Released exopolysaccharide (r-EPS) produced from probiotic bacteria reduce biofilm formation of enterohemorrhagic Escherichia coli O157:H7.
abstract: Here, we characterized released-exopolysaccharides (r-EPS) from Lactobacillus acidophilus A4 with the goal of identifying natural compounds that represses biofilm formation. In plastic 96-well microplates that contained 1.0 mg/ml of r-EPS, enterohemorrhagic Escherichia coli (EHEC) biofilms were dramatically decreased by 87% and 94% on polystyrene and polyvinyl chloride (PVC) surfaces, respectively. In the presence of r-EPS, neither their growth rate nor their autoinducer-2-like activity was affected on the EHEC O157:H7. Importantly, consistent reduction in biofilm formation was also observed when r-EPS was applied to the continuous-flow chamber models. In addition, we found that adding r-EPS significantly repressed biofilm formation by affecting genes related to curli production (crl, csgA, and csgB) and chemotaxis (cheY) in transcriptome analysis. Furthermore, these r-EPS could prevent biofilm formation by a wide range of Gram-negative and -positive pathogens. This property may lead to the development of novel food-grade adjuncts for microbial biofilm control.
authors.affiliation: Division of Food Bioscience and Technology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Younghoon
authors.initials: Y
authors.lastname: Kim
authors.forename: Sejong
authors.initials: S
authors.lastname: Oh
authors.forename: Sae Hun
authors.initials: SH
authors.lastname: Kim
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D018441:Biofilms / Q000254:growth & development*; D045744:Cell Line, Tumor; D002633:Chemotaxis / Q000235:genetics; D004927:Escherichia coli Infections / Q000276:immunology*; D019453:Escherichia coli O157 / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D007779:Lactobacillus acidophilus / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D011137:Polystyrenes; D011143:Polyvinyl Chloride; D019936:Probiotics
chemical_list: D001426:Bacterial Proteins; D011135:Polysaccharides, Bacterial; D011137:Polystyrenes; C077481:Crl protein, Bacteria; D011143:Polyvinyl Chloride