Dataset Information

The temperature-regulation of Pseudomonas aeruginosa cmaX-cfrX-cmpX operon reveals an intriguing molecular network involving the sigma factors AlgU and SigX

ABSTRACT: Pseudomonas aeruginosa is a highly adaptable Gram-negative opportunistic pathogen, notablydue to its large number of transcription regulators. The extracytoplasmic sigma factor (ECF sigma AlgU, responsible for alginate biosynthesis, is also involved in responses to cell wall stress and heat shock via the RpoH alternative sigma factor. The SigX ECF sigma emerged as a major regulator involved in the envelope stress response via membrane remodelling, virulence and biofilm formation. However, their functional interactions to coordinate the envelope homeostasis in response to environmental variations remain to be determined. The regulation of the putative cmaX-cfrX-cmpX operon located directly upstream sigX was investigated by applying sudden temperature shifts from 37°C. We identified a SigX- and an AlgU- dependent promoter region upstream of cfrX and cmaX, respectively. We show that cmaX expression is increased upon heat shock through an AlgU-dependent but RpoH independent mechanism. In addition, the ECF sigma SigX is activated in response to valinomycin, an agent altering the membrane structure, and up-regulates cfrX-cmpX transcription in response to cold shock. Altogether, these data provide new insights into the regulation exerted by SigX and networks that are involved in maintaining envelope homeostasis.

INSTRUMENT(S): autoflex

ORGANISM(S): Pseudomonas Aeruginosa Pao1

SUBMITTER: Emeline Bouffartigues

LAB HEAD: Prof Marc Feuilloley

PROVIDER: PXD021299 | Pride | 2020-10-05

REPOSITORIES: Pride

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The Temperature-Regulation of <i>Pseudomonas aeruginosa cmaX-cfrX-cmpX</i> Operon Reveals an Intriguing Molecular Network Involving the Sigma Factors AlgU and SigX.

Bouffartigues Emeline E Si Hadj Mohand Ishac I Maillot Olivier O Tortuel Damien D Omnes Jordane J David Audrey A Tahrioui Ali A Duchesne Rachel R Azuama Cecil Onyedikachi CO Nusser Michael M Brenner-Weiss Gerald G Bazire Alexis A Connil Nathalie N Orange Nicole N Feuilloley Marc G J MGJ Lesouhaitier Olivier O Dufour Alain A Cornelis Pierre P Chevalier Sylvie S

Frontiers in microbiology 20201021

<i>Pseudomonas aeruginosa</i> is a highly adaptable Gram-negative opportunistic pathogen, notably due to its large number of transcription regulators. The extracytoplasmic sigma factor (ECFσ) AlgU, responsible for alginate biosynthesis, is also involved in responses to cell wall stress and heat shock via the RpoH alternative σ factor. The SigX ECFσ emerged as a major regulator involved in the envelope stress response via membrane remodeling, virulence and biofilm formation. However, their functi ...[more]

PMID: 33193206

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			Action	DRS
	1r_spot_1.1r	Other
	1r_spot_2.1r	Other
	1r_spot_3.1r	Other
	1r_spot_4.1r	Other
	1r_spot_5.1r	Other