Bacterial Biofilms
May 07, 2015
Bacterial Biofilms
What’s a biofilm?
A biofilm is a structured community of microorganisms encapsulated within a self-developed polymeric matrix and adherent to a living or inert surface.
Biofilms are also often characterized by surface attachment, structural heterogeneity, genetic diversity, complex community interactions, and an extracellular matrix of
polymeric substances.
Examples
Biofilms are ubiquitous.
Biofilms can be found on rocks and pebbles at the bottom of most streams or rivers and often form on the surface of stagnant pools of water.
Biofilms grow in hot, acidic pools in Yellowstone National Park (USA) and on glaciers in Antarctica.
Biofilms in showers (Legionella).
Plaque formation on teeth.
Why a biofilm?
AdvantagesProtects the bacteria
AntibioticsPhagocytisedMetabolically inactiveSecretes virulence factors
Pseudomonas aeruginosa
Gram negative rod
Opportunistic pathogen
Fluoresces on certain types of agar
Prevalent in Hospitals due to it resistance to disinfectants
Particular problem in the cystic fibrosis community
Antibiotic resistant
Forms biofilms
Biofilm formation
Development initiates:plank tonic attached to biotic or abiotic surfaces.
Cells undergo a program of physiological changes involving Quorum sensing.
Production of copious quantities of extracellular polysaccharides.
Our Interest
Macrophage migration inhibitory factor (MIF)Enhance Pseudomonas aeruginosa growth both in vivo & in vitro
HypothesisMIF enhances biofilm formation
Culture Pseudomonas aeruginosa+/-MIF +/- OxygenBiofilm formation
Resazurin assay
Micro Arrays looking at gene expression
Possibilities
Target MIF therapeutically?InhibitorsDisrupt biofilm formationAntibiotics time to work
New antimicrobial defence for CF patients