ExsE, a secreted regulator of type III secretion genes in Pseudomonas aeruginosa
Arne Rietsch1, Isabelle Vallet-Gely, Simon L Dove
1Department of Microbiology and Molecular Genetics, Harvard Medical School, and Division of Infectious Diseases, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA.
Abstract:
Type III secretion systems are toxin delivery systems that are present in a large number of pathogens. A hallmark of all type III secretion systems studied to date is that expression of one or more of their components is induced upon cell contact. It has been proposed that this induction is controlled by a negative regulator that is itself secreted by means of the type III secretion machinery. Although candidate proteins for this negative regulator have been proposed in a number of systems, for the most part, a direct demonstration of their role in regulation is lacking. Here, we report the discovery of ExsE, a negative regulator of type III secretion gene expression in Pseudomonas aeruginosa. Deletion of exsE deregulates expression of the type III secretion genes. We provide evidence that ExsE is itself secreted by means of the type III secretion machinery and physically interacts with ExsC, a positive regulator of the type III secretion regulon. Taken together, these data demonstrate that ExsE is the secreted negative regulator that couples triggering of the type III secretion machinery to induction of the type III secretion genes.
More Related Videos
08:34Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection
Published on: January 8, 2020
04:37Detection and Quantification of Mono-Rhamnolipids and Di-Rhamnolipids Produced by Pseudomonas aeruginosa
Published on: March 29, 2024
Related Concept Videos
Prokaryotic Transcriptional Activators and Repressors
Transcription of prokaryotic...
Gram-negative Bacterial Protein Secretion Systems
Gene Regulation in Microbial Communities: Quorum Sensing
Stringent Response in E. coli
Other Stress Responses in Bacteria
Regulation of Bacterial Virulence
