Biomolecular NMR Assignments

, Volume 4, Issue 1, pp 33–36 | Cite as

NMR assignment and backbone dynamics of the pore-forming domain of colicin A

  • Alain Ibañez de Opakua
  • Tammo Diercks
  • Ana R. VigueraEmail author
  • Francisco J. BlancoEmail author


Colicin A protein kills cells by opening voltage-dependent ion channels in the cytoplasmic membrane. The C-terminal domain of colicin A retains the full protein’s ability to form membrane pores, making it an excellent model for in vitro studies of protein-membrane interaction. We report here the NMR assignment and backbone dynamics of this domain in solution. The chemical shifts identify ten α-helices that match those observed in the crystal structure, while the 15N{1H} NOEs show differential fast mobility for some of the inter-helical loops and the chain ends. This analysis provides the basis for further NMR studies of this channel forming protein and its interactions.


Colicin A Membrane pore Toxin Membrane insertion NMR assignment 



This work was funded by grant CTQ2008-03115/BQU to FJB from the Spanish Ministerio de Ciencia e Innovación (MCI) and BFU2006-14423/BMC (MEC).


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.Unidad de Biofísica (CSIC-UPV/EHU)Leioa-VizcayaSpain
  2. 2.Structural Biology UnitCIC bioGUNEDerioSpain

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