Spontaneous transfer of ganglioside GM/sub 1/ between phospholipid vesicles

Journal Article · Tue Aug 25 04:00:00 EDT 1987 · Biochemistry; (United States)

OSTI ID:5880472

Brown, R E; Thompson, T E

The transfer kinetics of the negatively charged glycosphingolipid II/sup 3/-N-acetylneuraminosyl-gangliotetraosylceramide (GM/sub 1/) were investigated by monitoring tritiated GM/sub 1/ movement between donor and acceptor vesicles. After appropriate incubation times at 45 /sup 0/C, donor and acceptor vesicles were separated by molecular sieve chromatography. Donors were small unilamellar vesicles produced by sonication, whereas acceptors were large unilamellar vesicles produced by either fusion or ethanol injection. Initial GM/sub 1/ transfer to acceptors followed first-order kinetics with a half-time of about 40 h assuming that GM/sub 1/ is present in equal mole fractions in the exterior and interior surfaces of the donor vesicle bilayer and that no glycolipid flip-flop occurs. GM/sub 1/ net transfer was calculated relative to that of (/sup 14/C)cholesteryl oleate, which served as a nontransferable marker in the donor vesicles. Factors affecting the GM/sub 1/ interbilayer transfer rate included phospholipid matrix composition, initial GM/sub 1/ concentration in donor vesicles, and the GM/sub 1/ distribution in donor vesicles with respect to total lipid symmetry. The findings provide evidence that GM/sub 1/ is molecularly dispersed at low concentrations within liquid-crystalline phospholipid bilayers.

• Research Organization: Univ. of Virginia School of Medicine, Charlottesville
• OSTI ID: 5880472
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 26:17; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
BIOCHEMICAL REACTION KINETICS
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CHROMATOGRAPHY
ESTERS
GANGLIOSIDES
GAS CHROMATOGRAPHY
GLYCOLIPIDS
KINETICS
LABELLED COMPOUNDS
LIPIDS
MEMBRANE TRANSPORT
MEMBRANES
MONOCARBOXYLIC ACIDS
OLEIC ACID
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
REACTION KINETICS
SACCHARIDES
SEPARATION PROCESSES
TRITIUM COMPOUNDS