Role of Sphingomonas sp. strain Fr1 PhyR-NepR-σEcfG cascade in general stress response and identification of a negative regulator of PhyR.

ABSTRACT: The general stress response in Alphaproteobacteria was recently described to depend on the alternative sigma factor σ(EcfG), whose activity is regulated by its anti-sigma factor NepR. The response regulator PhyR, in turn, regulates NepR activity in a partner-switching mechanism according to which phosphorylation of PhyR triggers sequestration of NepR by the sigma factor-like effector domain of PhyR. Although genes encoding predicted histidine kinases can often be found associated with phyR, little is known about their role in modulation of PhyR phosphorylation status. We demonstrate here that the PhyR-NepR-σ(EcfG) cascade is important for multiple stress resistance and competitiveness in the phyllosphere in a naturally abundant plant epiphyte, Sphingomonas sp. strain Fr1, and provide evide

SUBMITTER: Kaczmarczyk A 

PROVIDER: S-EPMC3232908 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature