What is a biofilm?

A biofilm is best defined as a structured community of microorganisms adherent to a surface. This definition encompasses the complexity involved in biofilm formation, as it reflects not just the presence of microorganisms, but also their organization and interaction within a shared environment.

Biofilms can consist of various types of bacteria, fungi, and even protozoa that become embedded in a self-produced matrix of extracellular polymeric substances (EPS). These structures may form on a range of surfaces, including medical devices, natural aquatic environments, and living tissues. The adherence to a surface is crucial, as it allows for the establishment of a stable community where microorganisms can communicate, share resources, and exhibit behaviors that would not occur in a planktonic (free-floating) state.

This inherent organization leads to increased resistance to environmental stresses including antibiotics and immune responses, illustrating the significance of biofilms in various pathogenic contexts. Understanding biofilms is critical in fields such as infectious disease, industrial microbiology, and environmental science, given their impact on health and industry.