Potent bacterial adhesin that mediates bacterial attachment to a broad variety of human and other mammalian cells. AIDA possesses additional virulence properties, as it is capable of mediating bacterial autoaggregation via intercellular self-recognition and it is a highly efficient initiator of biofilm formation. Intercellular AIDA-AIDA interaction is responsible for bacterial autoaggregation. AIDA can also interact with antigen 43 (Ag43), and the resultant intercellular AIDA-Ag43 interaction causes cell aggregation. The N-terminal passenger domain containing the adhesin moiety gains access to the surface. The cleaved AIDAc containing the translocator domain is localized in the outer membrane. The signal peptide, cleaved at the inner membrane, guides the polyprotein to the periplasmic space. Then, insertion of the C-terminal translocator domain (or beta-domain) in the outer membrane forms a hydrophilic pore for the translocation of the passenger domain to the bacterial cell surface, with subsequent autocatalytic cleavage. Finally, the mature AIDA protein remains in contact with the cell surface via non-covalent interactions with the translocator pore. Glycosylated with an average of 19 heptose residues. Only the glycosylated form binds to mammalilan cells. But glycosylation of AIDA is not required for AIDA-mediated cell-cell aggregation, interaction with Ag43, and induction of biofilm formation.