Fimbrial Adhesins: Adhesive Molecules on a 'Stalk'
Hae Joo Kang, Edward N. Baker and Thomas Proft
from: Bacterial Pathogenesis: Molecular and Cellular Mechanisms (Edited by: Camille Locht and Michel Simonet). Caister Academic Press, U.K. (2012)
As an important step for the successful and continuous colonization of the host, bacterial pathogens express a variety of specific adhesins on their cell surface, which allows them to interact with receptors on host cells. However, this close interaction might also be detrimental for the bacteria, as it could trigger infiltration and activation of immune cells and eventually lead to phagocytosis. Another obstacle for colonization is electrostatic repulsion due to the negative surface charge on both the bacteria and the host cell. Many bacteria have overcome this problem by expressing adhesins at the tip of a long fibril structure that extends from the bacterial cell surface. These structures are known as fimbriae or pili. Despite their diversity in structure and biogenesis, pili/fimbriae typically consist of a long fiber formed by homopolymerised subunits or pilins, and accessory pilins that often function as adhesins. Some pili are also involved in cell aggregation, biofilm formation, DNA uptake, phage transduction and gliding motility read more ...