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1H, 15N and 13C resonance assignments and secondary structure of PulG, the major pseudopilin from Klebsiella oxytoca type 2 secretion system


Bacteria use complex transporters to secrete functionally relevant proteins to the extracellular medium. The type 2 secretion system (T2SS) translocates folded proteins involved in bacterial nutrient acquisition, virulence and adaptation. The T2SS pseudopilus is a periplasmic filament, assembled by the polymerization of PulG subunits, the major pseudopilin. Pseudopilin proteins have a conserved N-terminal hydrophobic segment followed by a more variable C-terminal periplasmic and globular domain. To better understand the mechanism of assembly and function of the T2SS, we have been studying the structure and dynamics of PulG by NMR, as well as its interaction with other components of the secretion machinery. As a first step on this study, here we reported the chemical shift assignments of PulG C-terminal domain and its secondary structure prediction based on NMR data.

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This work was funded by the Institut Pasteur, the Centre National de la Recherche Scientifique (CNRS) and a FiberSpace Grant (No. ANR-14-CE09-0004) from the Agence Nationale de la Recherche (ANR). ALC was funded by the ANR grant. We thank Catherine Simenel for expert help in setting up the NMR experiments. Financial support from the TGIR-RMN-THC Fr3050 CNRS is also gratefully acknowledged.

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Correspondence to Aracelys López-Castilla or Nadia Izadi-Pruneyre.

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The experiments comply with the current laws of France.

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López-Castilla, A., Vitorge, B., Khoury, L. et al. 1H, 15N and 13C resonance assignments and secondary structure of PulG, the major pseudopilin from Klebsiella oxytoca type 2 secretion system. Biomol NMR Assign 11, 155–158 (2017).

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  • Chemical shift assignments
  • Type 2 secretion system
  • PulG
  • Major pseudopilin
  • Klebsiella oxytoca
  • Secondary structure