Biofilm

Definition

A biofilm is a complex aggregation of microorganisms growing on a surface, encased in a self-produced matrix of extracellular polymeric substances (EPS). These communities are highly resistant to antimicrobial agents and can be found in various environments, including medical devices and human tissues.

5 Must Know Facts For Your Next Test

1. Biofilms can form on both living and non-living surfaces, including medical implants such as catheters and joint prostheses.
2. The EPS matrix provides protection to the microorganisms within the biofilm from antibiotics and the host's immune system.
3. Infections associated with biofilms are often chronic and difficult to eradicate due to their resistance to antimicrobial treatments.
4. Biofilms play a significant role in dental plaque formation, contributing to oral diseases such as cavities and periodontal disease.
5. Biofilm formation is a key factor in the pathogenicity of many bacteria, aiding in their ability to colonize and persist in hostile environments like the urogenital tract.

Review Questions

• What components make up the extracellular polymeric substances (EPS) in a biofilm?
• Why are biofilms more resistant to antimicrobial agents compared to planktonic (free-floating) bacteria?
• How do biofilms contribute to infections associated with medical devices?

Related terms

Extracellular Polymeric Substances (EPS): A complex mixture of polysaccharides, proteins, nucleic acids, and lipids that form the matrix surrounding cells within a biofilm.

Planktonic Bacteria: Free-floating bacterial cells that live independently rather than as part of a community like those in biofilms.

Chronic Infection: An infection that persists over time, often associated with biofilm formation due to increased resistance to treatment.