This family consists of several AfaD and related proteins from Escherichia coli and Salmonella bacteria. The afa gene clusters encode an afimbrial adhesive sheath produced by Escherichia coli. The adhesive sheath is composed of two proteins, AfaD and AfaE, which are independently exposed at the bacterial cell surface. AfaE is required for bacterial adhesion to HeLa cells and AfaD for the uptake of adherent bacteria into these cells [1].

1: Characterization of the AfaD-like family of invasins encoded by pathogenic Escherichia coli associated with intestinal and extra-intestinal infections. Garcia MI, Jouve M, Nataro JP, Gounon P, Le Bouguenec C; FEBS Lett 2000;479:111-117. PMID:10981717