Fimbriae

Definition

Fimbriae are hair-like appendages present on the surface of many bacteria, primarily involved in adhesion to surfaces and other cells. They play a significant role in bacterial colonization and virulence.

5 Must Know Facts For Your Next Test

1. Fimbriae differ from pili; fimbriae are shorter and more numerous.
2. They are crucial for bacterial adherence to host tissues, enhancing infection potential.
3. Fimbriae can be involved in biofilm formation, contributing to microbial growth and persistence.
4. Pathogenic bacteria use fimbriae to attach to mucosal surfaces during infections of the gastrointestinal tract.
5. Some bacteria have specialized fimbriae that recognize specific host receptors, increasing their virulence.

Review Questions

• How do fimbriae contribute to bacterial pathogenicity?
• What is the difference between fimbriae and pili?
• In what ways can fimbriae affect microbial growth?

Related terms

Pili:

Longer, tubular structures that can transfer genetic material between bacterial cells.

Biofilm:

A complex community of microorganisms adhering to a surface, encased in an extracellular matrix.

Adhesins:

Molecules on the surface of pathogens that enable them to bind to host cells or tissues.