1. Background Biofilm: community of microorganisms attached to a surface
Biofouling: the process by which unwanted material accumulates on a surface

2. Extracellular Polymeric Substance
Composition of EPS synthesized varies from microbe to microbe
Functional role in microbial survival i.e. adhesion, protection
Critical for the structure and survival of the biofilm
Determines the micro-habitat of the cells within the biofilm
Influenced by the surrounding environment
Flemming, 2011

3. Extracellular Polymeric Substance
EPS of microbial origin are a complex mixture of biopolymers comprising polysaccharides, proteins, nucleic acids, uronic acids, humic substances, lipids…
Bacterial secretions
Shedding of cell surface materials
Cell lysates
Adsorption of organic constituents from
the environment
result in EPS formation in a wide variety of
free-living bacteria as well as microbial
aggregates like biofilms, bioflocs and
biogranules.
Pal & Paul, 2008

4. Biofilm formation EPS has a role in all parts of biofilm formation
Vogeleer et al., 2014
EPS has a role in all parts of biofilm formation
Aids in the adhesion to surfaces
Formation of complexes
Dissolution of the biofilm
Limoli et al, 2015

5. Transparent exopolymer particles
Sub group of extracellular polymeric substance
Organic microgels of various sizes
Present in marine and fresh water
Colonised by microorganisms
Naturally produced by phytoplankton and bacteria.
TEP stained with alcian blue
Bar-zeev et al, 2012
Bar-zeev et al, 2012

6. Role of EPS & TEP in biofouling
Bar-Zeev et al., 2015

7. References
Bar-Zeev, E., Berman-Frank, I., Girshevitzb, O., Berman, T., 2012, Revised paradigm of aquatic biofilm formation facilitated by microgel transparent exopolymer particles, PNAS, 109: 9119 – 9124.
Bar-Zeev, E., Passow, U., Castrillon, S. R-V., Elimelech, M., 2015, Transparent Exopolymer Particles: From Aquatic Environments and Engineered Systems to Membrane Biofouling, Envir. Sci. & Tech., 49: 691 – 707.
Flemming, H. C The perfect slime, Colloids and Surfaces B: Biointerfaces, 86: 251 – 259.
Limoli, D.H., Jones, C. J., Wozniak, D. J., 2015, Bacterial extracellular polysaccharides in biofilm formation and function, Microbiol. Spectrum, 1 – 19.
Pal, A., Paul, A.K., 2008, Microbial extracellular polymeric substances: central elements in heavy metal bioremediation, Indian J. Microbiol., 48:49–64.
Vogeleer, P., Tremblay, Y. D. N., Mafu, A. A. Jacques, M., Harel, J., 2014,
Life on the outside: role of biofilms in environmental persistence of Shiga-toxin producing Escherichia coli, Frontiers in microbiol., 5: 1 – 12.