title: YsxC, an essential protein in Staphylococcus aureus crucial for ribosome assembly/stability.
abstract: BACKGROUND
  Bacterial growth and division requires a core set of essential proteins, several of which are still of unknown function. They are also attractive targets for the development of new antibiotics. YsxC is a member of a family of GTPases highly conserved across eubacteria with a possible ribosome associated function.
  
  
  RESULTS
  Here, we demonstrate by the creation of a conditional lethal mutant that ysxC is apparently essential for growth in S. aureus. To begin to elucidate YsxC function, a translational fusion of YsxC to the CBP-ProteinA tag in the staphylococcal chromosome was made, enabling Tandem Affinity Purification (TAP) of YsxC-interacting partners. These included the ribosomal proteins S2, S10 and L17, as well as the beta' subunit of the RNA polymerase. YsxC was then shown to copurify with ribosomes as an accessory protein specifically localizing to the 50 S subunit. YsxC depletion led to a decrease in the presence of mature ribosomes, indicating a role in ribosome assembly and/or stability in S. aureus.
  
  
  CONCLUSIONS
  In this study we demonstrate that YsxC of S. aureus localizes to the ribosomes, is crucial for ribosomal stability and is apparently essential for the life of S. aureus.
authors.affiliation: Department of Molecular Biology and Microbiology, University of Sheffield, Sheffield S10 2TN, UK. elizabeth_cooper@merck.com
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Cooper
authors.forename: Jorge
authors.initials: J
authors.lastname: García-Lara
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Foster
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology*; D002846:Chromatography, Affinity; D015169:Colony Count, Microbial; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D020043:Genes, Essential; D006801:Humans; D050296:Microbial Viability; D011485:Protein Binding; D025941:Protein Interaction Mapping; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification; D054681:Ribosome Subunits, Large, Bacterial / Q000737:chemistry / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D020558:GTP Phosphohydrolases