Yop-YscD-cpl is the cytoplasmic domain of Yop proteins like YscD from Proteobacteria. YscD forms part of the inner membrane component of the bacterial type III secretion injectosome apparatus [1,2].

1: Analysis of virC, an operon involved in the secretion of Yop proteins by Yersinia enterocolitica. Michiels T, Vanooteghem JC, Lambert de Rouvroit C, China B, Gustin A, Boudry P, Cornelis GR; J Bacteriol 1991;173:4994-5009. PMID:1860816

2: Structure of the cytoplasmic domain of Yersinia pestis YscD, an essential component of the type III secretion system. Lountos GT, Tropea JE, Waugh DS; Acta Crystallogr D Biol Crystallogr. 2012;68:201-209. PMID:22349221