9/18/2016 Biofilms Defined-a community of microbes associated with a surface and typically encased in an extracellular polymeric substance matrix or EPS d Biofilm:a Multi-Step Process Cells in a biofilm are more resistant to heat,chemicals,and sanitizers than are planktonic cells First recognized in 1684 by Antonie van Leeuwenhoek 1-Planktoric bocteria 2-Surfoce attachment 3-Microcolony Dental caries as the biofilm Vinegar as the antimicrobial + Planktonic cells showed no motility -After vinegar wash,plaque bacteria still motile 4-Macrecolory 5-Detachment vater filled voids heterogeneity.stobilized coordinates activities Dental plaque 10 9/18/2016 10 Biofilms Defined - a community of microbes associated with a surface and typically encased in an extracellular polymeric substance matrix or EPS biofilm on a piece of lettuce 37 Campylobacter cells attached to chicken juice 38 Biofilm: a Multi-Step Process - motility - random contacts - appendages - EPS matrix - nutrient dependent growth - cell-cell binding interactions 1-Planktonic bacteria 2-Surface attachment 3-Microcolony water filled voids, heterogeneity, stabilized by the EPS matrix, quorum sensing coordinates activities 4-Macrocolony 5-Detachment 39 Cells in a biofilm are more resistant to heat, chemicals, and sanitizers than are planktonic cells First recognized in 1684 by Antonie van Leeuwenhoek - Dental caries as the biofilm - Vinegar as the antimicrobial - Planktonic cells showed no motility - After vinegar wash, plaque bacteria still motile Dental plaque40