Albany 2013: Book of Abstracts

category image Albany 2013
Conversation 18
June 11-15 2013
©Adenine Press (2012)

Designing Stiff Protein Nanopores for Challenging Tasks in Biosensing

Protein nanopore-based sensing elements represent a pressing need in molecular biomedical diagnosis (Bayley & Cremer, 2001). However, the integration of protein nanopores with other nanofluidic devices is a challenging task. This is especially true if we consider that isolated single proteins are in general fragile and unstable under harsh conditions of detection. Here, I will present a strategy for improving the stability of the open-state current of a redesigned nanopore using ferric hydroxamate uptake component A (FhuA), a beta-barrel membrane protein channel of E. coli (Mohammad, Iyer, Howard, McPike, Borer & Movileanu, 2012). The primary function of FhuA is to facilitate the energy-driven, high-affinity Fe3+ uptake complexed by the siderophore ferrichrome (Pawelek, Croteau, Ng-Thow-Hing, Khursigara, Moiseeva, Allaire & Coulton, 2006). The key ingredient of this strategy was the coupling of direct genetic engineering of FhuA with a fast-dilution refolding approach to obtain an unusually stable protein nanopore under a broad range of experimentation. These advantageous characteristics were recently demonstrated by examining proteolytic activity of an enzyme at a highly acidic pH, a condition at which majority of beta-barrel protein nanopores are normally gated or unfolded. Future membrane protein design work will not only reveal a better understanding of the processes employed in membrane protein folding and stability, but will also serve as a platform for the integration of robust protein components into devices (Astier, Bayley & Howorka, 2005).


  1. Y. Astier, H. Bayley and S. Howorka (2005). Protein components for nanodevices. Curr. Opin. Chem. Biol. 9, 576-584.
  2. H. Bayley & P. S. Cremer (2001). Stochastic sensors inspired by biology. Nature 413, 226-230.
  3. M.M. Mohammad, R. Iyer, K. R. Howard, M. P. McPike, P. N. Borer & L. Movileanu (2012). Engineering a Rigid Protein Tunnel for Biomolecular Detection. J. Am. Chem. Soc. 134, 9521-9531.
  4. P.D. Pawelek, N. Croteau, C. Ng-Thow-Hing, C. M. Khursigara, N. Moiseeva, M. Allaire & J. W. Coulton (2006). Structure of TonB in complex with FhuA, E. coli outer membrane receptor. Science 312, 1399-1402.

L. Movileanu

Department of Physics, Syracuse University, 201 Physics Bldg, Syracuse, NY 13244-1130

Ph: (315) 443-8078
Fx: (315) 443-9103
Email: lmovilea@physics.syr.edu