A secreted regulatory protein couples transcription to the secretory activity of the Pseudomonas aeruginosa type III secretion system.

ABSTRACT: The type III secretion system (T3SS) of Pseudomonas aeruginosa is an important virulence determinant. Transcription of the T3SS is highly regulated and intimately coupled to the activity of the type III secretion channel. The secretion channel is generally closed, and transcription is repressed. Inducing signals such as calcium depletion, however, open the secretion channel and derepress transcription of the T3SS. The coupling of transcription with secretion requires three previously identified cytoplasmic regulatory proteins. ExsA is a DNA-binding protein required for transcriptional activation of the entire T3SS. The second regulatory protein, ExsD, functions as anti-activator by directly binding to ExsA. Finally, ExsC functions as an anti-anti-activator by directly binding to and inhibi

SUBMITTER: Urbanowski ML 

PROVIDER: S-EPMC1175016 | biostudies-literature | 2005 Jul

REPOSITORIES: biostudies-literature