Polymicrobial biofilm (PMB)

Polymicrobial biofilms are complex, three-dimensional communities of diverse microorganisms, such as bacteria and fungi, that are encased within a self-produced matrix of extracellular polymeric substances (EPS) (NIH, 2021). These communities are characterized by intricate social interactions, including metabolic cooperation and horizontal gene transfer, which enhance the survival of the constituent species against environmental stressors (Nature Reviews Microbiology, 2018). In clinical settings, polymicrobial biofilms are a primary cause of chronic and persistent infections, notably in cystic fibrosis, diabetic foot ulcers, and on prosthetic medical devices (StatPearls, 2023). The structural integrity of the biofilm provides a physical and chemical barrier that renders the microorganisms significantly more resistant to antibiotics compared to their planktonic counterparts (PubMed, 2020). Drugs targeting these biofilms often focus on disrupting the EPS matrix, inhibiting quorum sensing pathways, or using enzymes like DNase to degrade extracellular DNA (Journal of Bacteriology, 2020). Effective treatment typically requires a combination of biofilm-disrupting agents and high-dose antimicrobials to ensure complete eradication and prevent the emergence of resistant strains. Understanding the spatial organization and inter-species dynamics within these biofilms is essential for developing precision therapies that can penetrate the protective barrier and neutralize the underlying infection.

Other names

Mixed-species biofilmMulti-species biofilmMicrobial communityConsortium biofilmInfection-associated biofilmDental plaque

Disruption of the extracellular polymeric substance (EPS) matrix, inhibition of quorum sensing signaling, degradation of extracellular DNA (eDNA), and enhancement of antimicrobial penetration through physical or chemical destabilization of the biofilm structure.