Fimbriae, Transmembrane Signaling, and Cell Activation

Abstract
Attachment to mucosal surfaces enables commensal organisms to select their ecologic niche and pathogens to select their site of infection. The tissue-specific attachment involves the coupling of microbial surface adhesins to receptor epitopes on host cell surfaces and may occur in competition with soluble receptor molecules. Gram-negative bacteria carry fimbriae with lectin-like domains that recognize receptor epitopes in cell surface glycolipids or glycoproteins. The resulting specific adherence may enhance bacterial persistence at the site of infection, but adherence also has been identified as a virulence factor that facilitates tissue attack, invasion, and mucosal inflammation