Members of this family adopt a secondary structure consisting of a beta sandwich, with nine strands arranged in two sheets in a Greek key topology. They are predominantly found in bacterial mannose-specific adhesins, since they are capable of binding to D-mannose [1].

1: Structural basis of tropism of Escherichia coli to the bladder during urinary tract infection. Hung CS, Bouckaert J, Hung D, Pinkner J, Widberg C, DeFusco A, Auguste CG, Strouse R, Langermann S, Waksman G, Hultgren SJ; Mol Microbiol. 2002;44:903-915. PMID:12010488