biofilme

Biofilms are communities of microorganisms encased in a self-produced matrix of extracellular polymeric substances (EPS). This matrix, composed of polysaccharides, proteins, nucleic acids, and lipids, adheres to surfaces and protects the embedded microbes from environmental stresses, such as antibiotics, disinfectants, and immune system responses. Biofilms can form on a wide range of surfaces, both living and non-living, in diverse environments including soil, water, industrial equipment, and medical implants.

The formation of a biofilm is a complex, multi-step process. Initially, free-swimming microorganisms attach reversibly to a surface. This is followed by irreversible attachment, where cells anchor more firmly and begin to multiply. Next, the microorganisms produce the EPS matrix, which encases the growing community and allows for cell-to-cell communication, known as quorum sensing. Finally, the mature biofilm may release planktonic cells, which can then colonize new surfaces.

Biofilms are significant in various fields. In medicine, they are implicated in numerous persistent infections, such as those associated with medical devices like catheters and prosthetic joints, and chronic conditions like cystic fibrosis lung infections and periodontitis. Their resistance to antimicrobial agents makes them challenging to eradicate. In industry, biofilms can cause fouling and corrosion in pipelines and water systems, leading to economic losses and operational inefficiencies. Conversely, biofilms play beneficial roles in natural ecosystems, such as nutrient cycling in soil and water treatment processes. Research is ongoing to develop effective strategies for controlling pathogenic biofilms and harnessing the beneficial properties of others.