Biochemical characterization of extracellular polymeric substances from endodontic biofilms

Abstract

Apical periodontitis is frequently associated with the presence of bacteria biofilm, which has an indisputable impact on the prognosis of endodontic therapy due to the high resistance to adverse environmental conditions, chemicals, and antibiotic therapy that characterize bacteria within biofilm. The biofilm matrix acts as a protective shield over the encased microorganisms. The aim of this investigation was to identify the main biochemical components of biofilm matrix from endodontic mono- and dual-species biofilms. Enterococcus faecalis and Actinomyces naeslundii were cultured as mono- and dual-species biofilms for 14 days. Crude extracellular polymeric substances (EPSs) from biofilm matrices were extracted using chemical and physical methods. High-performance liquid chromatography, gas chromatography, and mass spectrometry were used to determine the carbohydrate, protein, and fatty acid components. Chemical analysis of the biofilm matrices revealed that they were mainly composed of stachyose, maltose, and mannose carbohydrates. The protein profile in all biofilm samples showed abundant oxidoreductases and chaperone proteins and some virulence- associated proteins mainly located in the membrane surface. High percentages of saturated and monounsaturated fatty acids were identified in all biofilm matrices, with a major prevalence of palmitic, stearic, and oleic acids. Based on the results, it was possible to obtain for the first time a general overview of the biochemical profile of endodontic biofilm matrices.

Raman Spectroscopic Characterization of Endodontic Biofilm Matrices

“…In a previous research, we found that biochemical composition among these biofilms species varies significantly from monospecies to dual species [38]. A major fraction of polysaccharides, proteins, and fatty acids was identified in the monospecies biofilms compared to those in the dual-species biofilms [38]. ese results indicate that the two species influence each other at the biochemical level, and further data support the synergistic action between these two endodontic pathogens [39].…”

“…In a previous research, we found that biochemical composition among these biofilms species varies significantly from monospecies to dual species [38]. A major fraction of polysaccharides, proteins, and fatty acids was identified in the monospecies biofilms compared to those in the dual-species biofilms [38].…”

“…As a preliminary study, our results showed variations in wave shape confirming the difference in the chemical composition of analysed biofilms, although more data are obviously required on the biofilm molecular composition when grown on biological surfaces including dentin or hydroxyapatite. It is of interest to examine metabolic activities of bacteria during the maturation of the biofilm process, especially in mixed populations where interspecies interactions show different chemical behavior [29,38].…”

Activity of Antimicrobial Peptides and Ciprofloxacin against Pseudomonas aeruginosa Biofilms

“…Biofilms are multi-layered, localized, organized and heterogenous networks of microorganisms surrounded by self-produced extracellular polymeric substances (EPS) containing biomolecules such as polysaccharides, proteins, nucleic acids, and lipids [ 1 , 2 ]. Biofilms cause 80% of human bacterial infections, including biomaterial-associated infections, lung infections in cystic fibrosis patients and wound infections [ 3 , 4 ].…”

Characterization of Biofilm Extracts from Two Marine Bacteria

“…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]. Enzymatic digestion can also be applied to recover a targeted component [35,36].In this study, we were interested in the biofilms formed by two Vibrio species known to produce exopolysaccharides in bioreactors.…”