Membrane structure and dynamics as viewed by solid-state NMR spectroscopy

The purpose of the present study is the investigation of the structure and dynamics of biological membranes using solid-state nuclear magnetic resonance (NMR) spectroscopy. Two approaches are used in our laboratory. The first involves the measurement of high-resolution C-13 and H-1 spectra obtained by the magic angle spinning (MAS) technique while the second approach involves the measurement of P-31 and H-2 powder spectra in static samples, This paper will present some recent results obtained by high-resolution solid-state H-1 NMR on the conformation of gramicidin A incorporated in a phosphatidylcholine bilayers. More specifically, we were able to observe changes in the gramicidin spectra as a function of the cosolubilization solvent initially used to prepare the samples. The interaction between lipid bilayers and an anticancer drug derived from chloroethylurea was also investigated using proton NMR spectroscopy. Finally, we have studied the interaction between cardiotoxin, a toxic protein extracted from snake venom, and negatively charged lipid bilayers using P-31 solid-state NMR spectroscopy. (C) 1997 Elsevier Science B.V.