Journal of Biomolecular NMR

, Volume 15, Issue 3, pp 213–225

Solvation study of the non-specific lipid transfer protein from wheat by intermolecular NOEs with water and small organic molecules

  • Edvards Liepinsh
  • Patrick Sodano
  • Severine Tassin
  • Didier Marion
  • Françoise Vovelle
  • Gottfried Otting
Article

DOI: 10.1023/A:1008331519459

Cite this article as:
Liepinsh, E., Sodano, P., Tassin, S. et al. J Biomol NMR (1999) 15: 213. doi:10.1023/A:1008331519459

Abstract

Intermolecular nuclear Overhauser effects (NOEs) were measured between the protons of various small solvent or gas molecules and the non-specific lipid transfer protein (ns-LTP) from wheat. Intermolecular NOEs were observed with the hydrophobic pocket in the interior of wheat ns-LTP, which grew in intensity in the order cyclopropane (saturated solution) < methane (140 bar) < ethane (40 bar) < acetonitrile (5% in water) < cyclohexane (saturated solution) < benzene (saturated solution). No intermolecular NOEs were observed with dioxane (5% in water). The intermolecular NOEs were negative for all of the organic molecules tested. Intermolecular NOEs between wheat ns-LTP and water were weak or could not be distinguished from exchange-relayed NOEs. As illustrated by the NOEs with cyclohexane versus dioxane, the hydrophobic pocket in wheat ns-LTP preferably binds non-polar molecules. Yet, polar molecules like acetonitrile can also be accommodated. The pressure dependence of the NOEs between methane and wheat ns-LTP indicated incomplete occupancy, even at 190 bar methane pressure. In general, NOE intensities increased with the size of the ligand molecule and its vapor pressure. NMR of the vapor phase showed excellent resolution between the signals from the gas phase and those from the liquid phase. The vapor concentration of cyclohexane was fivefold higher than that of the dioxane solution, supporting the binding of cyclohexane versus uptake of dioxane.

gas phase NMRhomonuclear pulse sequencesintermolecular NOElipid transfer proteinnon-polar cavityoccupancyprotein hydrationprotein–solvent interaction

Supplementary material

Copyright information

© Kluwer Academic Publishers 1999

Authors and Affiliations

  • Edvards Liepinsh
    • 1
  • Patrick Sodano
    • 2
  • Severine Tassin
    • 2
  • Didier Marion
    • 3
  • Françoise Vovelle
    • 2
  • Gottfried Otting
    • 1
  1. 1.Department of Molecular Biochemistry and BiophysicsKarolinska InstitutetStockholmSweden
  2. 2.Centre de Biophysique Moléculairerue Charles SadronOrléans Cedex 02France
  3. 3.Laboratoire de Biochimie et Technologie des ProteinesINRANantes Cedex 05France