The Temperature-Regulation of Pseudomonas aeruginosa cmaX-cfrX-cmpX Operon Reveals an Intriguing Molecular Network Involving the Sigma Factors AlgU and SigX
| Autor: | Gerald Brenner-Weiss, Alexis Bazire, Olivier Maillot, Ishac Si Hadj Mohand, Cecil Onyedikachi Azuama, Sylvie Chevalier, Ali Tahrioui, Damien Tortuel, Michael Nusser, Emeline Bouffartigues, Rachel Duchesne, Nathalie Connil, Jordane Omnes, Olivier Lesouhaitier, Pierre Cornelis, Nicole Orange, Alain Dufour, Audrey David, Marc G. J. Feuilloley |
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| Přispěvatelé: | Vriendenkring VUB, Microbiology |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Microbiology (medical)
Life sciences biology Operon Regulator lcsh:QR1-502 Virulence medicine.disease_cause Microbiology lcsh:Microbiology 03 medical and health sciences Transcription (biology) Sigma factor ddc:570 medicine 030304 developmental biology 0303 health sciences 030306 microbiology Pseudomonas aeruginosa Chemistry membrane fluidity Biofilm temperature Promoter Cell biology regulation of transcription cell wall stress ECF sigma factor |
| Zdroj: | Frontiers in microbiology, 11, Art. Nr.: 579495 Frontiers in Microbiology, Vol 11 (2020) |
| ISSN: | 1664-302X |
| Popis: | Pseudomonas aeruginosa 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 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 ECFσ 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. |
| Databáze: | OpenAIRE |
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