RRC ID 35270
Author Jovanovic G, Engl C, Mayhew AJ, Burrows PC, Buck M.
Title Properties of the phage-shock-protein (Psp) regulatory complex that govern signal transduction and induction of the Psp response in Escherichia coli.
Journal Microbiology (Reading)
Abstract The phage-shock-protein (Psp) response maintains the proton-motive force (pmf) under extracytoplasmic stress conditions that impair the inner membrane (IM) in bacterial cells. In Escherichia coli transcription of the pspABCDE and pspG genes requires activation of σ(54)-RNA polymerase by the enhancer-binding protein PspF. A regulatory network comprising PspF-A-C-B-ArcB controls psp expression. One key regulatory point is the negative control of PspF imposed by its binding to PspA. It has been proposed that under stress conditions, the IM-bound sensors PspB and PspC receive and transduce the signal(s) to PspA via protein-protein interactions, resulting in the release of the PspA-PspF inhibitory complex and the consequent induction of psp. In this work we demonstrate that PspB self-associates and interacts with PspC via putative IM regions. We present evidence suggesting that PspC has two topologies and that conserved residue G48 and the putative leucine zipper motif are determinants required for PspA interaction and signal transduction upon stress. We also establish that PspC directly interacts with the effector PspG, and show that PspG self-associates. These results are discussed in the context of formation and function of the Psp regulatory complex.
Volume 156(Pt 10)
Pages 2920-2932
Published 2010-10-1
DOI 10.1099/mic.0.040055-0
PMID 20595257
PMC PMC3068692
MeSH Escherichia coli / genetics* Escherichia coli / metabolism Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Gene Expression Regulation, Bacterial Leucine Zippers Membrane Proteins / genetics Membrane Proteins / metabolism* Signal Transduction*
IF 1.922
Times Cited 27
Prokaryotes E. coli JW1296-KC