Biofilms

Definition

Biofilms are complex communities of microorganisms that adhere to surfaces and are embedded within a self-produced matrix of extracellular polymeric substances. They provide protection to the bacteria from environmental stresses and antimicrobial agents.

5 Must Know Facts For Your Next Test

1. Biofilms can form on both living and non-living surfaces, including medical devices like catheters and prosthetic joints.
2. The development of biofilms involves four stages: initial attachment, irreversible attachment, maturation, and dispersion.
3. Bacteria within biofilms exhibit different gene expression compared to their planktonic (free-floating) counterparts, often leading to increased resistance to antibiotics.
4. Common locations for biofilm formation in the human body include teeth (dental plaque), lungs (in cystic fibrosis patients), and chronic wounds.
5. Microscopic techniques such as confocal laser scanning microscopy are often used to visualize and study biofilms.

Review Questions

• What are the four stages of biofilm development?
• Why do bacteria in biofilms have increased resistance to antibiotics compared to free-floating bacteria?
• Name three common locations in the human body where biofilm formation occurs.

Related terms

Extracellular Polymeric Substances (EPS): A complex mixture of polymers secreted by microorganisms in a biofilm, providing structural stability.

Planktonic Cells: Free-floating microbial cells that live independently rather than in a community like a biofilm.

Confocal Laser Scanning Microscopy: A powerful imaging technique used to obtain high-resolution images of thick specimens like biofilms.