Members of this family are composed of two pairs of parallel alpha-helices, and interact with the bacterial protein YopN via hydrophobic residues located on the helices. Association of TyeA with the C terminus of YopN is accompanied by conformational changes in both polypeptides that create order out of disorder: the resulting structure then serves as an impediment to type III secretion of YopN [1].

1: Three-dimensional structure of a macromolecular assembly that regulates type III secretion in Yersinia pestis. Schubot FD, Jackson MW, Penrose KJ, Cherry S, Tropea JE, Plano GV, Waugh DS; J Mol Biol. 2005;346:1147-1161. PMID:15701523