Bacterial cell surface and extracellular biofilm matrix (EPS matrix)

The bacterial cell surface and extracellular biofilm matrix constitute a complex, protective microenvironment that shields microbial communities from host immune defenses and antimicrobial agents. The matrix is primarily composed of extracellular polymeric substances (EPS), including exopolysaccharides, proteins, lipids, and extracellular DNA (eDNA), which provide structural stability and facilitate surface attachment (Flemming & Wingender, 2010, Nature Reviews Microbiology). This assembly acts as a physical and chemical barrier, contributing to the high levels of antibiotic tolerance observed in chronic infections such as those associated with cystic fibrosis, indwelling medical devices, and non-healing wounds (Hall-Stoodley et al., 2004, Nature Reviews Microbiology). Therapeutic targeting of the matrix involves the use of enzymes like DNase I (Dornase alfa) to degrade eDNA or glycosyl hydrolases to break down polysaccharides, thereby destabilizing the biofilm architecture (Tetz & Tetz, 2010, Antimicrobial Agents and Chemotherapy). By disrupting these surfaces, drugs aim to increase the susceptibility of the encased bacteria to conventional antibiotics and facilitate their clearance by the host immune system (Karygianni et al., 2020, Frontiers in Cellular and Infection Microbiology).

Other names

Extracellular polymeric substancesBiofilm matrixBacterial glycocalyxMicrobial extracellular matrixSlime layer

Enzymatic degradation of extracellular DNA and polysaccharides, chelation of stabilizing divalent cations, inhibition of matrix synthesis, and disruption of cell wall/membrane integrity to enhance antibiotic penetration and immune clearance.