Global control of bacterial translation by a specific ribosomal modification

ABSTRACT: Translational regulation plays a critical role in controlling the environmental responses of diverse bacterial species. In addition to existing, well-established regulatory pathways, the alteration of ribosome function by specific posttranslational modification represents a potential further mechanism for translational control. Although numerous ribosomal proteins undergo diverse posttranslational modifications, in most cases the functional and physiological significance of these changes remains unclear. The datasets presented here support our discovery that the widespread ribosomal modification protein RimK functions as a previously uncharacterized global controller of bacterial mRNA translation. RimK modification of the ribosomal protein RpsF changes both the stability and function of the bacterial ribosome and alters the composition of the bacterial proteome. In addition to multiple ribosomal proteins, rimK deletion in the biocontrol bacterium Pseudomonas fluorescens leads to significantly reduced levels of the important translational regulators Hfq and RsmE. This in turn leads to increased production of ABC transporters, stress response proteins and non-ribosomal peptide synthetases. Deletion of rimK compromises wheat rhizosphere colonization by P. fluorescens and significantly reduces virulence in the phytopathogen Pseudomonas syringae. Critically, the expression of P. fluorescens rimK is not constitutive, but varies throughout wheat rhizosphere colonisation, peaking during initial niche colonisation and declining in the established rhizosphere. Differential modification of the ribosome through temporal control of RimK expression represents a novel regulatory mechanism by which Pseudomonas fine-tunes its proteome to appropriately respond to the surrounding environment.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Pseudomonas Fluorescens (strain Sbw25)

TISSUE(S): Cell Suspension Culture

SUBMITTER: Gerhard Saalbach  

LAB HEAD: Jacob George Malone

PROVIDER: PXD001371 | Pride | 2016-02-17

REPOSITORIES: Pride