Virulence Fimbriae, Pili, Flagella and Bacterial Virulence

Fimbriae, Pili, Flagella and Bacterial Virulence
Main characteristic
? the ability of bacteria to bind to cells from potential host organisms.
? Fimbriated and piliated bacteria agglutinated erythrocytes in a fashion resembling classical hemagglutination and adhered to host epithelial cells
? Moreover, for some strains bacteria-induced hemagglutination was inhibited by the addition of the monosaccharide mannose. This suggested that mannose is used as a receptor for adherence and that the free mannose functions as a hapten
? For other bacteria-erythrocyte reactions hemagglutination was not inhibited by mannose implying another receptor selectivity in the binding reaction
? fimbriae or pili function as specific adhesive that aid bacterial colonization of mucosal surfaces.
Functions:
1. Fimbriae are known to bind plasma proteins and to initiate proteolytic cascades
2. others are capable of activating calcium influx and signal transduction cascades in host target cells
3. fimbriae have been shown to act as invasion and motility factors
4. bacterial flagella that typically mediate bacterial motility have also function bacteria adherence and in the initiation of proinflammatory responses.
Classification & biosynthesis
All adhesive factors show typically fimbrial in morphology they showed receptor – specific binding abilities. Fimbriae and flagella share the need to a polymer architecturally outside the ordinary bacterial anabolic machinery.
Fimbriae, Pili, Flagella and Bacterial Virulence
Main characteristic
? the ability of bacteria to bind to cells from potential host organisms.
? Fimbriated and piliated bacteria agglutinated erythrocytes in a fashion resembling classical hemagglutination and adhered to host epithelial cells
? Moreover, for some strains bacteria-induced hemagglutination was inhibited by the addition of the monosaccharide mannose. This suggested that mannose is used as a receptor for adherence and that the free mannose functions as a hapten
? For other bacteria-erythrocyte reactions hemagglutination was not inhibited by mannose implying another receptor selectivity in the binding reaction
? fimbriae or pili function as specific adhesive that aid bacterial colonization of mucosal surfaces.
Functions:
1. Fimbriae are known to bind plasma proteins and to initiate proteolytic cascades
2. others are capable of activating calcium influx and signal transduction cascades in host target cells
3. fimbriae have been shown to act as invasion and motility factors
4. bacterial flagella that typically mediate bacterial motility have also function bacteria adherence and in the initiation of proinflammatory responses.
Classification & biosynthesis
All adhesive factors show typically fimbrial in morphology they showed receptor – specific binding abilities. Fimbriae and flagella share the need to a polymer architecturally outside the ordinary bacterial anabolic machinery.