Correlation Engine 2.0
Clear Search sequence regions

  • bacteria (2)
  • cell (2)
  • cell wall (1)
  • cellular (1)
  • circular dichroism (1)
  • crystal (1)
  • dna (2)
  • enterococcus (2)
  • enterococcus faecalis (1)
  • genes (1)
  • gram (2)
  • host (1)
  • human (1)
  • models molecular (1)
  • plasmid (4)
  • T4S (1)
  • T4SSs (3)
  • TraK (2)
  • wall cell (1)
  • Sizes of these terms reflect their relevance to your search.

    Conjugative plasmid transfer presents a serious threat to human health as the most important means of spreading antibiotic resistance and virulence genes among bacteria. The required direct cell-cell contact is established by a multi-protein complex, the conjugative type IV secretion system (T4SS). The conjugative core complex spans the cellular envelope and serves as a channel for macromolecular secretion. T4SSs of Gram-negative (G-) origin have been studied in great detail. In contrast, T4SSs of Gram-positive (G+) bacteria have only received little attention thus far, despite the medical relevance of numerous G+ pathogens (e.g. enterococci, staphylococci and streptococci). This study provides structural information on the type IV secretion (T4S) protein TraK of the G+ broad host range Enterococcus conjugative plasmid pIP501. The crystal structure of the N-terminally truncated construct TraKΔ was determined to 3.0 Å resolution and exhibits a novel fold. Immunolocalization demonstrated that the protein localizes to the cell wall facing towards the cell exterior, but does not exhibit surface accessibility. Circular dichroism, dynamic light scattering and size-exclusion chromatography confirmed the protein to be a monomer. With the exception of proteins from closely related T4SSs, no significant sequence or structural relatives were found. This observation marks the protein as a very exclusive, specialized member of the pIP501 T4SS.


    Nikolaus Goessweiner-Mohr, Christian Fercher, Karsten Arends, Ruth Birner-Gruenberger, Diana Laverde-Gomez, Johannes Huebner, Elisabeth Grohmann, Walter Keller. The type IV secretion protein TraK from the Enterococcus conjugative plasmid pIP501 exhibits a novel fold. Acta crystallographica. Section D, Biological crystallography. 2014 Apr;70(Pt 4):1124-35

    Expand section icon Mesh Tags

    Expand section icon Substances

    PMID: 24699656

    View Full Text