The biofilm matrix

Wingender, J., Neu, T. & Flemming, H.-C. in Microbial Extracellular Polymeric Substances (eds Wingender, J., Neu, T. & Flemming, H.-C.) 1–19 (Springer, Heidelberg, 1999).

Karatan, E. & Watnik, P. Signals, regulatory networks, and materials that build and break bacterial biofilms. Microbiol. Mol. Biol. Rev. 73, 310–347 (2009). An excellent paper on aspects of the regulation of the biofilm matrix.

Xavier, J. B. & Foster, K. R. Cooperation and conflict in microbial biofilms. Proc. Natl Acad. Sci. USA 104, 876–881 (2007). An important and inspiring discussion on microbial interactions, including the role of the matrix.

Flemming, H. C., Neu, T. R. & Wozniak, D. The EPS matrix: the house of biofilm cells. J. Bacteriol. 189, 7945–7947 (2007).

Allison, D. G., Sutherland, I. W. & Neu, T. R. in Biofilm Communities: Order from Chaos? (eds McBain, A. et al.) 381–387 (BioLine, Cardiff, 1998).

Zogaj, X., Nimtz, M., Rohde, M., Bokranz, W. & Römling, U. The multicellular morphotypes of Salmonella typhimurium and Escherichia coli produce cellulose as the second component of the extracellular matrix. Mol. Microbiol. 39, 1452–1463 (2001).

Schooling, S. R. & Beveridge, T. J. Membrane vesicles: an overlooked component of the matrices of biofilms. J. Bacteriol. 188, 5945–5957 (2006).

Decho, A. W. Microbial exopolymer secretions in ocean environments: their role(s) in food webs and marine processes. Oceanogr. Mar. Biol. Annu. Rev. 28, 73–153 (1990). A classic review of microbial interactions, including the role of EPS.

Decho, A. W. Microbial biofilms in intertidal systems: an overview. Cont. Shelf Res. 20, 1257–1273 (2000).

Flemming, H.-C. & Wingender, J. in Encyclopedia of Environmental Microbiology (ed. Bitton, G.) 1223–1231 (Wiley, New York, 2002).

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Sutherland, I. W. The biofilm matrix – an immobilized but dynamic microbial environment. Trends Microbiol. 9, 222–227 (2001).

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Lawrence, J. R., Swerhone, G. D. W., Kuhlicke, U. & Neu, T. R. In situ evidence for microdomains in the polymer matrix of bacterial microcolonies. Can. J. Microbiol. 53, 450–458 (2007). The use of lectin-staining analysis for characterizing target structures in the EPS matrix.

Wagner, M., Ivleva, N. P., Haisch, C., Niessner, R. & Horn, H. Combined use of confocal laser scanning microscopy (CLSM) and Raman microscopy (RM): investigations on EPS-matrix. Water Res. 43, 63–76 (2009).

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Tielen, P., Strathmann, M., Jaeger, K. E., Flemming, H.-C. & Wingender, J. Alginate acetylation influences initial surface colonization by mucoid Pseudomonas aeruginosa. Microbiol. Res. 160, 165–176 (2005).

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Wozniak, D. et al. Alginate is not a significant component of the extracellular polysaccharide matrix of PA14 and PAO1 Pseudomonas aeruginosa biofilms. Proc. Natl Acad. Sci. USA 100, 7907–7912 (2003).

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Nielsen, P. H. & Jahn, A. in Microbial Extracellular Polymeric Substances (eds Wingender, J., Neu, T. & Flemming, H.-C.) 49–72 (Springer, Heidelberg, 1999).

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Wingender. J., Strathmann, M., Rode, A., Leis, A. & Flemming, H.-C. Isolation and biochemical characterization of extracellular polymeric substances from Pseudomonas aeruginosa. Methods Enzymol. 336, 302–314 (2001).

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Tielker, D. et al. Pseudomonas aeruginosa lectin LecB is located in the outer membrane and is involved in biofilm formation. Microbiology 151, 1313–1323 (2005).

Diggle, S. P. et al. The galactophilic lectin, LecA, contributes to biofilm development in Pseudomonas aeruginosa. Environ. Microbiol. 8, 1095–1104 (2006).

Johansson, E. M. V. et al. Inhibition and dispersion of Pseudomonas aeruginosa biofilms by glycopeptide dendrimers targeting the fucose-specific lectin LecB. Chem. Biol. 15, 1249–1257 (2008).

Lasa, I. & Penadés, J. R. Bap: a family of surface proteins involved in biofilm formation. Res. Microbiol. 157, 99–107 (2006). A description of the role of non-enzymatic proteins in the biofilm matrix.

Otzen, D. & Nielsen, P. H. We find them here, we find them there: functional bacterial amyloid. Cell. Mol. Life Sci. 65, 910–927 (2007).

van Schaik, E. J. et al. DNA binding: a novel function of Pseudomonas aeruginosa type IV pili. J. Bacteriol. 187, 1455–1464 (2005).

Izano, E. A., Amarante, M. A., Kher, W. B. & Kaplan, J. B. Differential roles of poly-N-acetylglucosamine surface polysaccharide and extracellular DNA in Staphylococcus aureus and Staphylococcus epidermidis biofilms. Appl. Environ. Microbiol. 74, 470–476 (2008).

Molin, S. & Tolker-Nielsen, T. Gene transfer occurs with enhanced efficiency in biofilms and induces enhanced stabilisation of the biofilm structure. Curr. Opin. Biotechnol. 14, 255–261 (2003).

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Whitchurch, C. B., Tolker-Nielsen, T., Ragas, P. S. & Mattick, J. S. Extracellular DNA required for bacterial biofilm formation. Science 295, 1487 (2002). The first report on the functional relevance of eDNA to biofilms.

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Böckelmann, U. et al. Bacterial extracellular DNA forming a defined network-like structure. FEMS Microbiol. Lett. 262, 31–38 (2006).

Jurcisek, J. A. & Bakaletz, L. O. Biofilms formed by nontypeable Haemophilus influenzae in vivo contain both double-stranded DNA and type IV pilin protein. J. Bacteriol. 189, 3868–3875 (2007).

Steinberger, R. E. & Holden, P. A. Extracellular DNA in single- and multiple-species unsaturated biofilms. Appl. Environ. Microbiol. 71, 5404–5410 (2005).

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Neu, T. Significance of bacterial surface-active compounds in interactions of bacteria with interfaces. Microbiol. Rev. 60, 151–166 (1996). A valuable and comprehensive overview of the concept and ecological role of biosurfactants as part of the EPS matrix.

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