Protection of the general stress response σS factor by the CrsR regulator allows a rapid and efficient adaptation of Shewanella oneidensis.
J Biol Chem
; 292(36): 14921-14928, 2017 09 08.
Article
in En
| MEDLINE
| ID: mdl-28729423
ABSTRACT
To cope with environmental stresses, bacteria have evolved various strategies, including the general stress response (GSR). GSR is governed by an alternative transcriptional σ factor named σS (RpoS) that associates with RNA polymerase and controls the expression of numerous genes. Previously, we have reported that posttranslational regulation of σS in the aquatic bacterium Shewanella oneidensis involves the CrsR-CrsA partner-switching regulatory system, but the exact mechanism by which CrsR and CrsA control σS activity is not completely unveiled. Here, using a translational gene fusion, we show that CrsR sequesters and protects σS during the exponential growth phase and thus enables rapid gene activation by σS as soon as the cells enter early stationary phase. We further demonstrate by an in vitro approach that this protection is mediated by the anti-σ domain of CrsR. Structure-based alignments of CsrR orthologs and other anti-σ factors identified a CsrR-specific region characteristic of a new family of anti-σ factors. We found that CrsR is conserved in many aquatic proteobacteria, and most of the time it is associated with CrsA. In conclusion, our results suggest that CsrR-mediated protection of σS during exponential growth enables rapid adaptation of S. oneidensis to changing and stressful growth conditions, and this ability is probably widespread among aquatic proteobacteria.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sigma Factor
/
Stress, Physiological
/
Bacterial Proteins
/
Shewanella
Type of study:
Prognostic_studies
Language:
En
Journal:
J Biol Chem
Year:
2017
Document type:
Article
Affiliation country:
France