Anisotropic 2H-NMR spin-lattice relaxation in oriented bilayers of DMPC and DMPC + cholesterol

1992 ◽  
Vol 89 ◽  
pp. 237-242 ◽  
Author(s):  
MA Krajewski-Bertrand ◽  
Y Nakatani ◽  
G Ourisson ◽  
EJ Dufourc ◽  
A Milon
Keyword(s):  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice

NMR Studies of the Order and Dynamics of Dipalmitoylphosphatidylchoiine Bilayers as a Function of Pressure

1996 ◽  
Author(s):  
Ana Jonas ◽  
Xiangdong Peng
Keyword(s):  
Liquid Crystalline ◽  
Relaxation Times ◽  
Lateral Diffusion ◽  
Lattice Relaxation ◽  
Pressure Effects ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice ◽  
Spin Locking ◽  
Nmr Methods

We have used 2H NMR methods to examine the order and dynamics of dipalmitoylphosphatidylcholine (DPPC) in multilamellar and small unilamellar vesicles in water as a function of pressure. Multipulse 2H NMR techniques were used with selectively deuterated DPPC on both chains at positions C-2, C-9, or C-13, to obtain lineshapes, spin-lattice relaxation times (T1), and spin-spin relaxation times (T2) at 50 °C from 1 bar to 5.2 kbar pressure. This pressure range allowed us to explore the phase behavior of DPPC from the liquid crystalline (LC) phase through various gel phases (Gl, Gll, Glll, GX), including the interdigited Gi phase. Pressure has an ordering effect: on all chain segments in all the phases. In the LC phase, the order parameter (SCD) decreases from C-2 > C-9 > C-13, while in the gel phases SCD decreases from C-9 > C-13 > C-2, indicating that in the gel phases the middle segments of the chains are more restricted in their motions than the ends. In the LC phase, T1 and T2 values for all segments decrease with pressure and have an order from C-13 > C-9 > C-2. These results suggest that similar conformational motions and molecular rotational motions occur in the LC state in all segments, but have increased amplitudes and frequencies toward the methyl ends. At the phase transitions, discontinuities and abrupt reversal of the slopes for the T1 or T2 dependences on pressure indicate major changes in motional modes and rates for DPPC molecules in the different structures. In the second part of this study, we have measured the lateral diffusion of DPPC in sonicated vesicles in D2O as a function of pressure. The spin-lattice relaxation rate in the rotating frame T−11p was plotted as a function of the square root of the spin-locking field angular frequency (ω1)1/2, and the lateral diffusion coefficient (D) was calculated from the slope. Pressure effects are observed on lateral diffusion in the LC phase (D = 5.4 − 2 × 10−9 cm2 seconds, from 1 to 300 bar) but are negligible in the GI phase (D ≈ 1.0 × 10−9 cm2 seconds, from 400 to 800 bar).

Anisotropic spin-lattice relaxation in lipid bilayers: A solid state 2H NMR lineshape study

1985 ◽  
Vol 119 (2-3) ◽  
pp. 251-255 ◽  
Author(s):  
D.J. Siminovitch ◽  
M.J. Ruocco ◽  
E.T. Olejniczak ◽  
S.K. Das Gupta ◽  
R.G. Griffin
Keyword(s):  
Solid State ◽  
Lipid Bilayers ◽  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice

ChemInform Abstract: Tyrosyl Motion in Peptides: 2H NMR Line Shapes and Spin-Lattice Relaxation.

ChemInform ◽  
1987 ◽  
Vol 18 (30) ◽  
Author(s):  
D. M. RICE ◽  
Y. C. MEINWALD ◽  
H. A. SCHERAGA ◽  
R. G. GRIFFIN
Keyword(s):  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice ◽  
Line Shapes

2H NMR Line Shapes and Spin−Lattice Relaxation in Ba(ClO3)2·2H2O

1997 ◽  
Vol 101 (6) ◽  
pp. 988-994 ◽  
Author(s):  
Joanna R. Long ◽  
Rainer Ebelhäuser ◽  
R. G. Griffin
Keyword(s):  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice ◽  
Line Shapes

Dynamics of [Zn(D2O)6]2+ in [Zn(D2O)6][SiF6] crystal as studied by 1D, 2D spectra and spin-lattice relaxation time of 2H NMR

2008 ◽  
Vol 344 (3) ◽  
pp. 291-298 ◽  
Author(s):  
Takashi Araya ◽  
Akira Niwa ◽  
Motohiro Mizuno ◽  
Kazunaka Endo
Keyword(s):  
Relaxation Time ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice Relaxation Time ◽  
Spin Lattice

Nonexponential 2H-NMR Spin-Lattice Relaxation as a Signature of the Glassy State

1990 ◽  
pp. 80-81
Author(s):  
W. Schnauss ◽  
F. Fujara ◽  
K. Hartmann ◽  
H. Sillescu
Keyword(s):  
Glassy State ◽  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
2H Nmr ◽  
Spin Lattice
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