YscP and YscU switch the substrate specificity of the Yersinia type III secretion system by regulating export of the inner rod protein YscI.

ABSTRACT: Pathogenic yersiniae utilize a type III secretion system to inject antihost factors, called Yops, directly into the cytosol of eukaryotic cells. The Yops are injected via a needle-like structure, comprising the YscF protein, on the bacterial surface. While the needle is being assembled, Yops cannot be secreted. YscP and YscU switch the substrate specificity of the secretion system to enable Yop export once the needle attains its proper length. Here, we demonstrate that the inner rod protein YscI plays a critical role in substrate specificity switching. We show that YscI is secreted by the type III secretion system and that YscI secretion by a yscP mutant is abnormally elevated. Furthermore, we show that mutations in the cytoplasmic domain of YscU reduce YscI secretion by the yscP null stra

SUBMITTER: Wood SE 

PROVIDER: S-EPMC2446745 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature