Biofilms: structure, resistance mechanism, emerging control strategies, and applications

Biofilms are biological barriers produced by a variety of organisms either for defense or because of physiological processes. Many microorganisms produce biofilms to adapt to certain adverse conditions and this has resulted in difficulty in their eradication with antimicrobial agents. There is the increasing menace of antimicrobial resistance (AMR) by bacteria due to the production of biofilms. Specifically, bacterial biofilms are complex surface-delimited microbial structures contained in a matrix of extracellular polymeric substances, which are an obstacle to effective medical treatment of infections caused by these bacteria. Biofilm resistance to antibiotics can lead to persistent infections. Of particular concern are biofilms made from ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species), which are bacteria resistant to the action of many antimicrobial agents. Following the emergence of AMR attributed to biofilms, which complicates disease treatment options and increases morbidity and mortality, there is an urgent need to understand the underlying mechanism of the formation of biofilms, their structure and the resistance profiles, strategies, and barrier systems, which have not been sufficiently considered all together. This systematic review can enable the precipitation of findings and control strategies for the development of effective interventions, guide research efforts, and inform clinical practices in handling biofilms. This review focuses on the different characteristics of biofilms, the organization of biofilms, the life cycles, and various models for studying biofilms, as well as the ways through which biofilms can be resistant to antimicrobials. The strategies for biofilm management, the role played by biofilms in clinical practice, and promising paradigms for the assessment of the outcome will also be highlighted. With the knowledge of how biofilms function and their relation to pathogens, life scientists can more effectively develop management plans to eradicate biofilm-related infections and provide better patient care.