The Yersinia pseudotuberculosis degradosome is required for oxidative stress, while its PNPase subunit plays a degradosome-independent role in cold growth.
Yersinia polynucleotide phosphorylase (PNPase), a 3'-5' exoribonuclease, has been shown to affect growth during several stress responses. In Escherichia coli, PNPase is one of the subunits of a multiprotein complex known as the degradosome, but also has degradosome-independent functions. The carboxy-terminus of E. coli ribonuclease E (RNase E) serves as the scaffold upon which PNPase, enolase (a glycolytic enzyme), and RhlB helicase all have been shown to bind. In the yersiniae, only PNPase has thus far been shown to physically interact with RNase E. We show by bacterial two-hybrid and co-immunoprecipitation assays that RhlB and enolase also interact with RNase E. Interestingly, although PNPase is required for normal growth at cold temperatures, assembly of the yersiniae degradosome was not required. However, degradosome assembly was required for growth in the presence of reactive oxygen species. These data suggest that while the Yersinia pseudotuberculosis PNPase plays a role in the oxidative stress response through a degradosome-dependent mechanism, PNPase's role during cold stress is degradosome-independent.
Department of Biology, Center for Bionanotechnology and Environmental Research (CBER), Texas Southern University, Houston, TX, USA.
Amanda
A
Henry
Justin
J
Shanks
Ambro
A
van Hoof
Jason A
JA
Rosenzweig
D003080:Cold Temperature; D004722:Endoribonucleases / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D009097:Multienzyme Complexes / Q000378:metabolism*; D018384:Oxidative Stress; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D011117:Polyribonucleotide Nucleotidyltransferase / Q000737:chemistry / Q000378:metabolism*; D021122:Protein Subunits / Q000378:metabolism*; D020365:RNA Helicases / Q000378:metabolism*; D013312:Stress, Physiological; D015011:Yersinia pseudotuberculosis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*
D009097:Multienzyme Complexes; D021122:Protein Subunits; C111244:degradosome; D006861:Hydrogen Peroxide; D011117:Polyribonucleotide Nucleotidyltransferase; D004722:Endoribonucleases; D020365:RNA Helicases; D010751:Phosphopyruvate Hydratase