Mechanics of Bacterial Adhesion
Bacteria must withstand tremendous shearing forces when binding to host, such as those induced by coughing, chewing, or urination. Consequently, they have evolved some pretty remarkable adhesive structures to address these mechanical challenges. We have been focused on understanding the mechanics of adhesion in Gram-positive bacteria, with a particular interest in their extracellular protein appendages, notably their pili. Pili are micron-long fibrous structure that can withstand the highest forces known of any globular proteins. Moreover, Gram-positive pili harbor a slew of internal covalent bonds, including disulfide, isopeptide, and thioester bonds, that confer remarkable mechanical stabilities, folding properties, and covalent binding to ligands. How these unique mechanical features conspire to facilitate bacterial adhesion is a fundamental question with implications for the development of novel anti-adhesive drugs.