Constant helical pitch of the gramicidin channel in phospholipid bilayers

Biophys J. 1992 Mar;61(3):827-30. doi: 10.1016/S0006-3495(92)81888-X.

Abstract

X-ray diffraction has been applied in measuring the helical pitch of the gramicidin channel in oriented bilayers of dilauroylphosphatidylcholine (DLPC) and dimyristoylphosphatidylcholine (DMPC) at a polypeptide concentration of 9.1 mol %. The diffraction data show the helical pitch of gramicidin to be 4.7 +/- 0.2 A in both gel and liquid-crystalline phase bilayers, with and without monovalent cations. In addition, the width of the reflection due to the pitch of the helical gramicidin channel is consistent with a five turn helix.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Dimyristoylphosphatidylcholine*
  • Gramicidin / chemistry*
  • Ion Channels
  • Lipid Bilayers*
  • Models, Biological
  • Phosphatidylcholines*
  • Protein Conformation
  • X-Ray Diffraction

Substances

  • Ion Channels
  • Lipid Bilayers
  • Phosphatidylcholines
  • Gramicidin
  • 1,2-dilauroylphosphatidylcholine
  • Dimyristoylphosphatidylcholine