Virulence-associated antigens involved in adhesin have been identified in several organisms: Haemophilus influenzae biogroup aegyptius; Escherichia coli K1; EHEC E.coli; Actinobacillus actinomycetencomitans; Haemophilus somnus; Haemophilus ducreyi; EPEC E.coli; EA EC E.coli; uropathogenic E.coli; Shigella flexneri; Brucella melitensis; Brucella suis; Ralstonia solanacearum; Sinorhizobium meliloti; Bradorhizobium japonicum; and Burkholderia fungorum. Although the degree of sequence identity between the adhesins is low, they share a common arrangement of domains from N-terminus to C-terminus, namely: a leader peptide; a globular head; a coiled-coil region; and a transmembrane anchor region.