The crystal structures of the Salmonella type III secretion system tip protein SipD in complex with deoxycholate and chenodeoxycholate.

ABSTRACT: The type III secretion system (T3SS) is a protein injection nanomachinery required for virulence by many human pathogenic bacteria including Salmonella and Shigella. An essential component of the T3SS is the tip protein and the Salmonella SipD and the Shigella IpaD tip proteins interact with bile salts, which serve as environmental sensors for these enteric pathogens. SipD and IpaD have long central coiled coils and their N-terminal regions form α-helical hairpins and a short helix α3 that pack against the coiled coil. Using AutoDock, others have predicted that the bile salt deoxycholate binds IpaD in a cleft formed by the α-helical hairpin and its long central coiled coil. NMR chemical shift mapping, however, indicated that the SipD residues most affected by bile salts are located in a di

SUBMITTER: Chatterjee S 

PROVIDER: S-EPMC3047063 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature