TY - JOUR
T1 - Editing 13C-NMR spectra of membranes
AU - Montez, Bernard
AU - Oldfield, Eric
AU - Urbina, Julio A.
AU - Pekerar, Sara
AU - Husted, Cynthia
AU - Patterson, Jessica
N1 - Funding Information:
The National Neurological Research Bank is sponsored by NINDS/NIMH, National Multiple Sclerosis Society, Huntington's Disease Foundation, Comprehensive Epilepsy Program, Tourette Syndrome Association, Dystonia Medical Research Foundation, and Veteran's Health Services and Research Administration, Department of Veterans Affairs. We thank Dr. Jeffrey Forbes, Dwight Schwartz and Tim Bowers for their assistance. This work was supported in part by the United States Public Health Service (NIH grant GM-40426), by the American Heart Association (grant AHA 92-013340) with funds provided in part by the AHA Illinois Affiliate Inc. and by the Instituto Venezolano de Investigaciones Cientificas, Caracas, Venezuela (J.U., S.P.).
PY - 1993/11/7
Y1 - 1993/11/7
N2 - We report the carbon-13 'magic-angle' sample-spinning nuclear magnetic resonance (NMR) spectra of several lipid-water systems, under a variety of radiofrequency excitation conditions. Our results show that complex lipid or membrane spectra can be greatly simplified by using 'spectral editing' techniques. For example, in a 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)-water mesophase, the glycerol (C-1, C-2 and C-3) carbons are readily distinguished from the headgroup Cα, Cβ and Cγ carbons, on the basis of their mix-time behavior in a cross-polarization (CP) experiment, while in the more complex DMPC/cholesterol-water system, many of the more rigid cholesterol carbon resonances can be edited from the phospholipid peaks. In very complex systems, such as human myelin membranes, editing permits the unambiguous observation of the mobile lipid headgroup carbon resonances, as well as the much more rigid sterol ring carbons. We also report the observation of a large differential CP due to C-H vector 'magic-angle' orientational effects in the DMPC/desipramine system. Thus, both motional or orientational reduction of the C-H dipolar interaction can lead to considerable simplifications of complex membrane spectra, and are of interest from both spectral assignment and membrane dynamics aspects.
AB - We report the carbon-13 'magic-angle' sample-spinning nuclear magnetic resonance (NMR) spectra of several lipid-water systems, under a variety of radiofrequency excitation conditions. Our results show that complex lipid or membrane spectra can be greatly simplified by using 'spectral editing' techniques. For example, in a 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)-water mesophase, the glycerol (C-1, C-2 and C-3) carbons are readily distinguished from the headgroup Cα, Cβ and Cγ carbons, on the basis of their mix-time behavior in a cross-polarization (CP) experiment, while in the more complex DMPC/cholesterol-water system, many of the more rigid cholesterol carbon resonances can be edited from the phospholipid peaks. In very complex systems, such as human myelin membranes, editing permits the unambiguous observation of the mobile lipid headgroup carbon resonances, as well as the much more rigid sterol ring carbons. We also report the observation of a large differential CP due to C-H vector 'magic-angle' orientational effects in the DMPC/desipramine system. Thus, both motional or orientational reduction of the C-H dipolar interaction can lead to considerable simplifications of complex membrane spectra, and are of interest from both spectral assignment and membrane dynamics aspects.
KW - Excitation condition
KW - Lipid-water system
KW - Membrane
KW - NMR, C-
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U2 - 10.1016/0005-2736(93)90263-Y
DO - 10.1016/0005-2736(93)90263-Y
M3 - Article
C2 - 8218332
AN - SCOPUS:0027332368
SN - 0005-2736
VL - 1152
SP - 314
EP - 318
JO - BBA - Biomembranes
JF - BBA - Biomembranes
IS - 2
ER -