NMR model of PrgI-SipD interaction and its implications in the needle-tip assembly of the Salmonella type III secretion system.

ABSTRACT: Salmonella and other pathogenic bacteria use the type III secretion system (T3SS) to inject virulence proteins into human cells to initiate infections. The structural component of the T3SS contains a needle and a needle tip. The needle is assembled from PrgI needle protomers and the needle tip is capped with several copies of the SipD tip protein. How a tip protein docks on the needle is unclear. A crystal structure of a PrgI-SipD fusion protein docked on the PrgI needle results in steric clash of SipD at the needle tip when modeled on the recent atomic structure of the needle. Thus, there is currently no good model of how SipD is docked on the PrgI needle tip. Previously, we showed by NMR paramagnetic relaxation enhancement (PRE) methods that a specific region in the SipD coiled coil is t

SUBMITTER: Rathinavelan T 

PROVIDER: S-EPMC4108505 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature