/sup 31/P nuclear magnetic resonance chemical shielding tensors of phosphorylethanolamine, lecithin, and related compounds: applications to head-group motion in model membranes

Journal Article · Tue Mar 09 04:00:00 EST 1976 · Biochemistry; (United States)

OSTI ID:7356799

Kohler, S J; Klein, M P

/sup 31/P nuclear magnetic resonance (NMR) power spectra have been used to obtain the principal values of the chemical shielding tensors of dipalmitoyllecithin (DPL), dipalmitoylphosphatidylethanolamine, and several related organophosphate mono- and diesters. In addition, the principal values and orientation of the phosphorylethanolamine shielding tensor were determined from /sup 31/P NMR spectra of a single crystal. In all compounds studied the shielding tensors were clearly nonaxial. The monoester spectra are typified by the spectrum of phosphorylethanolamine with principal values of -67, -13, and 69 ppm relative to H/sub 3/PO/sub 4/. The diesters have a larger total anisotropy, as indicated by the DPL values of -81, -25, and 108 ppm. These data as well as the orientation of the phosphorylethanolamine shielding tensor are correlated with the electron density distribution as determined by the bonding pattern of the phosphate. The spectrum of a DPL--water (1:1) mixture at 52/sup 0/C has a shift anisotropy of 30 ppm and displays a shape characteristic of an axial tensor. This change from the rigid lattice DPL pattern is explained in terms of motional narrowing, and the shielding tensor data are used to interpret the motion of the phospholipid head group. Simple rotation about the P--O(glycerol) bond is excluded, and a more complex motion involving rotation about both the P--O(glycerol) and glycerol C(2)--C(3) bonds is postulated. (auth)

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 7356799
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 15:5; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
BIOLOGICAL MODELS
CELL CONSTITUENTS
CELL MEMBRANES
ESTERS
ISOTOPES
LIGHT NUCLEI
LIPIDS
MAGNETIC RESONANCE
MEMBRANES
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
PHOSPHORUS 31
PHOSPHORUS ISOTOPES
RESONANCE
STABLE ISOTOPES