Disparate molecular dynamics of plasmenylcholine and phosphatidylcholine bilayers

Journal Article · Tue Jul 28 04:00:00 EDT 1987 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00389a033· OSTI ID:5994854

Pak, J H; Bork, V P; Norberg, R E; Creer, M H; Wolf, R A; Gross, R W

The molecular dynamics of binary dispersions of plasmenylcholine/cholesterol and phosphatidylcholine/cholesterol were quantified by electron spin resonance (ESR) and deuterium magnetic resonance (/sup 2/H NMR) spectroscopy. The order parameter of both 5-doxylstearate (5DS) and 16-doxylstearate (16DS) was larger in vesicles comprised of plasmenylcholine in comparison to phosphatidylcholine in all temperatures studied. Similarly, the order parameter of plasmenylcholine vesicles was larger than that of phosphatidylcholine vesicles utilizing either spin-labeled phosphatidylcholine or spin-labeled plasmenylcholine as probes of molecular motion. The ratio of the low-field to the midfield peak height in ESR spectra of 16-doxylstearate containing moieties was lower in plasmenylcholine vesicles in comparison to phosphatidylcholine vesicles. /sup 2/H NMR spectroscopy demonstrated that the order parameter of plasmenylcholine was greater than that of phosphatidylcholine for one of the two diastereotopic deuterons located at the C-2 carbon of the sn-2 fatty acyl chain. The spin-lattice relaxation times for deuteriated plasmenylcholine and phosphatidylcholine in binary mixtures containing 0-50 mol % cholesterol varied nonmonotonically as a function of cholesterol concentration and were different for each phospholipid subclass. Taken together, the results indicate that the vinyl ether linkage in the proximal portion of the sn-1 aliphatic chain of plasmenylcholine has substantial effects on the molecular dynamics of membrane bilayers both locally and at sites spatially distant from the covalent alteration.

• Research Organization: Washington Univ., St. Louis, MO
• OSTI ID: 5994854
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 26:15; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ALCOHOLS
AMINES
AMMONIUM COMPOUNDS
BIOCHEMICAL REACTION KINETICS
CHOLESTEROL
CHOLINE
DEUTERIUM
DRUGS
ELECTRON SPECTRA
ELECTRON SPIN RESONANCE
ESTERS
HYDROGEN ISOTOPES
HYDROXY COMPOUNDS
ISOTOPES
KINETICS
LIGHT NUCLEI
LIPIDS
LIPOTROPIC FACTORS
MAGNETIC RESONANCE
MEMBRANES
MOLECULAR STRUCTURE
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
QUATERNARY COMPOUNDS
REACTION KINETICS
RELAXATION TIME
RESONANCE
SPECTRA
STABLE ISOTOPES
STEROIDS
STEROLS