Members of this family adopt a structure consisting of three four-stranded beta-sheets, each with a Greek key fold, with internal pseudo threefold symmetry. Thus they act as a receptor binding beta-prism, binding to insect-specific receptors of gut epithelial cells [1].

1: Structure of Cry2Aa suggests an unexpected receptor binding epitope. Morse RJ, Yamamoto T, Stroud RM; Structure. 2001;9:409-417. PMID:11377201