Functional subconformations in protein folding: evidence from single-channel experiments

Phys Rev Lett. 2006 Jan 27;96(3):038101. doi: 10.1103/PhysRevLett.96.038101. Epub 2006 Jan 23.


We study fluctuations in ion conductance and enzymatic rates of the sugar-specific channel-forming membrane protein, Maltoporin, at the single-molecule level. Specifically, we analyze time-persistent deviations in the transport parameters of individual channels from the multichannel averages and discuss our findings in the context of static disorder in protein folding. We show that the disorder responsible for variations in ion conductance does not affect sugar binding, suggesting that Maltoporin can exist in a wide set of fully functional, yet distinctly different, subconformations.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Outer Membrane Proteins
  • Carbohydrates / chemistry*
  • Computer Simulation
  • Diffusion
  • Ion Channel Gating*
  • Lipid Bilayers / chemistry*
  • Membrane Fluidity*
  • Models, Chemical*
  • Models, Molecular*
  • Porins
  • Porosity
  • Protein Conformation
  • Protein Folding
  • Receptors, Virus / chemistry*
  • Structure-Activity Relationship


  • Bacterial Outer Membrane Proteins
  • Carbohydrates
  • Lipid Bilayers
  • Porins
  • Receptors, Virus
  • maltoporins