Extracellular polymeric substances of biofilms: Suffering from an identity crisis

Abstract

Microbial biofilms can be both cause and cure to a range of emerging societal problems including antimicrobial tolerance, water sanitation, water scarcity and pollution. The identities of extracellular polymeric substances (EPS) responsible for the establishment and function of biofilms are poorly understood. The lack of information on the chemical and physical identities of EPS limits the potential to rationally engineer biofilm processes, and impedes progress within the water and wastewater sector towards a circular economy and resource recovery. Here, a multidisciplinary roadmap for addressing this EPS identity crisis is proposed. This involves improved EPS extraction and characterization methodologies, crossreferencing between model biofilms and full-scale biofilm systems, and functional description of isolated EPS with in situ techniques (e.g. microscopy) coupled with genomics, proteomics and glycomics. The current extraction and spectrophotometric characterization methods, often based on the principle not to compromise the integrity of the microbial cells, should be critically assessed, and more comprehensive methods for recovery and characterization of EPS need to be developed.

Enhancing the Thermo-Stability and Anti-Bacterium Activity of Lysozyme by Immobilization on Chitosan Nanoparticles

“…X and Y represent the amount of lysozyme initially added to the formulation and the unload lysozyme, respectively, whereas Z represents the weight of the nanoparticles. All assays were performed in triplicate independently and the data are shown as mean ± standard deviation [37].…”

Unravelling interspecies interactions across heterogeneities in complex biofilm communities

“…To fully understand the heterogeneity of biofilm communities, the EPS must be thoroughly examined. Seviour and colleagues discuss why EPS analyses are challenging and provide details on several approaches for EPS characterization (Seviour et al, 2019). Overcoming such obstacles and learning about the EPS production of individual community members will further our understanding of the specific roles of these members and their interactions in establishing the biofilm community.…”

Characterization of Biofilm Extracts from Two Marine Bacteria

“…It appears then that, while EPM substances act to provide structure for the biofilm, their biotechnological potential is broad. New applications and markets for these molecules, including extracellular polymer-based bioproducts, are expected [34].…”

“…It appears then that, while EPM substances act to provide structure for the biofilm, their biotechnological potential is broad. New applications and markets for these molecules, including extracellular polymer-based bioproducts, are expected [34].Biofilm recovery is the first step toward characterizing the specific metabolites. Subsequently, depending on whether the analysis targets a particular component or not, the samples can be homogenized, fractionated into separate cells and soluble components, usually via centrifugation, and/or submitted to extraction in aqueous or nonaqueous solvents [35][36][37][38][39].…”