Acid stress activation of the sigma(E) stress response in Salmonella enterica serovar Typhimurium.
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ABSTRACT:
SUBMITTER: Muller C
PROVIDER: S-EPMC4157319 | biostudies-other | 2009 Mar
REPOSITORIES: biostudies-other
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Acid stress activation of the sigma(E) stress response in Salmonella enterica serovar Typhimurium.
Muller Cécile C Bang Iel-Soo IS Velayudhan Jyoti J Karlinsey Joyce J Papenfort Kai K Vogel Jörg J Fang Ferric C FC
Molecular microbiology 20090123 5
The alternative sigma factor sigma(E) is activated by unfolded outer membrane proteins (OMPs) and plays an essential role in Salmonella pathogenesis. The canonical pathway of sigma(E) activation in response to envelope stress involves sequential proteolysis of the anti-sigma factor RseA by the PDZ proteases DegS and RseP. Here we show that sigma(E) in Salmonella enterica sv. Typhimurium can also be activated by acid stress. A sigma(E)-deficient mutant exhibits increased susceptibility to acid pH ...[more]
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