fimbriae

(noun)

Fine filaments of protein distributed over the surface of bacteria that are believed to be involved in attachment to solid surfaces or to other cells, and are essential for the virulence of some bacterial pathogens.

Related Terms

Examples of fimbriae in the following topics:

  • Adherence

    • Fimbriae are fine filaments of protein, just 3–10 nanometers in diameter and up to several micrometers in length.
    • Fimbriae are believed to be involved in attachment to solid surfaces or to other cells, and are essential for the virulence of some bacterial pathogens.
    • Most fimbriae of Gram-negative bacteria function as adhesins, but in many cases the actual adhesin is a minor subunit protein at the tip of the fimbriae.
    • In bacteriology, a fimbria (plural fimbriae; abbreviated FIM) is an appendage composed of curlin proteins that can be found on many Gram-negative and some Gram-positive bacteria that is thinner and shorter than a flagellum.
    • Review the role of adhesins, including fimbriae and the Dr family, in pathogenic bacteria

  • Pili and Pilus Assembly

    • The terms pilus and fimbria (Latin for "thread" or "fiber," plural: fimbriae) can be used interchangeably, although some researchers reserve the term pilus for the appendage required for bacterial conjugation.
    • A fimbria is a short pilus that is used to attach the bacterium to a surface.
    • Some fimbriae can contain lectins.
    • Other fimbriae bind to components of the extracellular matrix.
    • Fimbriae are found in both Gram-negative and Gram-positive bacteria.

  • Gene Inversion

    • Fimbrial adhesion by the type I fimbriae in E. coli undergoes site specific inversion to regulate the expression of fimA, the major subunit of the pili, depending on the stage of infection.

  • Slipped-Strand Mispairing

    • The opportunistic pathogen H. influenzae has two divergently oriented promoters in fimbriae geneshifA and hifB.

  • Whooping Cough

    • Its virulence factors include pertussis toxin, filamentous hæmagglutinin, pertactin, fimbria, and tracheal cytotoxin.

  • Pathogenic Escherichia coli

    • Uropathogenic E. coli use P fimbriae (pyelonephritis-associated pili) to bind urinary tract endothelial cells and colonize the bladder.

  • Immediate Direct Examination of Specimen

    • Electron microscopes can pinpoint additional features such as cell wall flagella, pili, and fimbriae.