Proteomic characterization of a pilR regulatory mutant of Azoarcus sp. strain BH72 with the aid of gel-based and gel-free approaches Academic Article Article uri icon


MeSH Major

  • Cell Transformation, Viral
  • Oncogenes
  • Receptors, Cell Surface


  • The proteome of the grass endophyte Azoarcus sp. strain BH72 was analyzed by a combination of gel-based methods by means of 2-DE and MS and a gel-free approach via LC-MS/MS. Among the identified 785 proteins, synthesis of around 100 conserved hypothetical proteins could be confirmed. Membrane proteins were detected at a higher rate in the gel-free than in the gel-based approach. The abundance of proteins in the constructed proteome reference map was analyzed and the 30 most abundant proteins were determined. The reference map was then used as a starting point to characterize the regulon under control of the response regulator PilR. PilR is part of the two-component regulatory system PilSR controlling type IV pilin gene (pilAB) expression in strain BH72, which was strongly decreased (19.7-fold) in the pilR-mutant. Changes of protein composition in the wild type and the regulatory mutant were compared by the gel-based and gel-free analyses. Proteins responsible for amino acid and energy metabolism, chaperones as well as proteins that are involved in iron metabolism and iron storage were present in a pilR-mutant at different levels than in the wild-type strain. Levels of the transcriptional regulator Flp were also dependent on PilR, indicating that PilR might be part of a hierarchical regulatory cascade. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

publication date

  • February 2010



  • Academic Article


Digital Object Identifier (DOI)

  • 10.1002/pmic.200900307

PubMed ID

  • 20013799

Additional Document Info

start page

  • 458

end page

  • 469


  • 10


  • 3