Fighting biofilms with lantibiotics and other groups of bacteriocins

Abstract

Biofilms are sessile communities of bacteria typically embedded in an extracellular polymeric matrix. Bacterial cells embedded in biofilms are inherently recalcitrant to antimicrobials, compared to cells existing in a planktonic state, and are notoriously difficult to eradicate once formed. Avenues to tackle biofilms thus far have largely focussed on attempting to disrupt the initial stages of biofilm formation, including adhesion and maturation of the biofilm. Such an approach is advantageous as the concentrations required to inhibit formation of biofilms are generally much lower than removing a fully established biofilm. The crisis of antibiotic resistance in clinical settings worldwide has been further exacerbated by the ability of certain pathogenic bacteria to form biofilms. Perhaps the most notorious biofilm formers described from a clinical viewpoint have been methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Pseudomonas aeruginosa, Gardnerella vaginalis and Streptococcus mutans, the latter of which is found in oral biofilms. Due to the dearth of novel antibiotics in recent decades, compounded by the increasing rate of emergence of resistance amongst pathogens with a propensity for biofilm formation, solutions are urgently required to mitigate these crises. Bacteriocins are a class of antimicrobial peptides, which are ribosomally synthesised and often are more potent than their antibiotic counterparts. Here, we review a selection of studies conducted with bacteriocins with the ultimate objective of inhibiting biofilms. Overall, a deeper understanding of the precise means by which a biofilm forms on a substrate as well as insights into the mechanisms by which bacteriocins inhibit biofilms is warranted.

Bacteriocins, Potent Antimicrobial Peptides and the Fight against Multi Drug Resistant Species: Resistance Is Futile?

“…Bacteriocins Pep 5 and epidermin produced by Staphylococcus epidermidis both demonstrated an inhibitory action against the adhesion of Staphylococcus species to the surfaces of silicon catheters [36]. Additionally, nisin has been reported to possess biofilm penetrating abilities potentially making it a useful tool in preventing or eradicating biofilm communities [40] on invasive medical devices. Preliminary investigative studies also suggest possible uses of nisin as antibacterial coatings on implantable medical devices [40].…”

“…Additionally, nisin has been reported to possess biofilm penetrating abilities potentially making it a useful tool in preventing or eradicating biofilm communities [40] on invasive medical devices. Preliminary investigative studies also suggest possible uses of nisin as antibacterial coatings on implantable medical devices [40]. In vivo animal studies have demonstrated the efficacy of lantibiotics for preventing and treating infectious disease.…”

“…Solid or liquid phase synthesis and in vivo biotechnology recombinant methods are typically used for the production of medical peptides. Due to the complex nature of bacteriocin peptides and the need for posttranslational modification however, such synthesis methods are costly and unrealistic for large scale production [40]. Furthermore, an additional issue with chemical synthesis is the long and/or hyper-hydrophobic peptide design that can self-aggregate, obstructing the elongation steps [25].…”

“…Bacteriocins have been successfully implemented as food preservatives with nisin "generally regarded as safe" (GRAS) by the Food and Drug Administration (FDA) where it is used to prevent to the germination of C. botulinum spores in cheese products [40] and growth of L. monocytogenes in refrigerated dairy [56]. Studies also described the activity of nisin against S. aureus, B. cereus and B. subtilis in processed cheese [57].…”

Production of Bioactive Peptides from Lactic Acid Bacteria: A Sustainable Approach for Healthier Foods

“…Bacteriocins could inhibit “quorum sensing” and therefore suppressing biofilm formation (Chopra, Singh, Jena, & Sahoo, ; Algburi et al., ); biofilms are polymeric matrix produced by microorganisms more of all related with pathogenic ones and recognized as a public health problematic (Simões, Simoes, & Vieira, ). Once biofilms are established by a microbial community, removing them is more difficult than preventing their formation; bacteriocins could work as a preventive measure for preventing biofilm formation in many industries (Mathur et al., ).…”