In:
Journal of Bacteriology, American Society for Microbiology, Vol. 194, No. 24 ( 2012-12-15), p. 6900-6908
Kurzfassung:
By coprecipitation, we identified RNA-binding proteins in the Gram-positive opportunistic pathogen Enterococcus faecalis known to be deficient of the RNA chaperone Hfq. In particular, we characterized one belonging to the cold shock protein (Csp) family (Ef2925) renamed CspR for cold shock protein RNA binding. Compared to the wild-type strain, the Δ cspR mutant was less virulent in an insect infection model ( Galleria mellonella ) and exhibited a decreased persistence in mouse kidneys and a low survival rate in peritoneal macrophages. As expected, we found that the Δ cspR mutant strain was more impaired in its growth than the parental strain under cold conditions and in its long-term survival under nutrient starvation. All these phenotypes were restored after complementation of the Δ cspR mutant. In addition, Western blot analysis showed that CspR was overexpressed under cold shock conditions and in the stationary phase. Since CspR may act as an RNA chaperone, putative targets were identified using a global proteomic approach completed with transcriptomic assays. This study revealed that 19 proteins were differentially expressed in the Δ cspR strain (9 upregulated, 10 downregulated) and that CspR mainly acted at the posttranscriptional level. These data highlight for the first time the role of the RNA-binding protein CspR as a regulator in E. faecalis and its requirement in stress response and virulence in this important human pathogen.
Materialart:
Online-Ressource
ISSN:
0021-9193
,
1098-5530
Sprache:
Englisch
Verlag:
American Society for Microbiology
Publikationsdatum:
2012
ZDB Id:
1481988-0
SSG:
12