Spontaneous transfer of ganglioside GM1 between phospholipid vesicles

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

DOI:https://doi.org/10.1021/bi00391a036· OSTI ID:5607578

Brown, R E; Thompson, T E

The transfer kinetics of the negatively charged glycosphingolipid II3-N-acetylneuraminosyl-gangliotetraosylceramide (GM1) were investigated by monitoring tritiated GM1 movement between donor and acceptor vesicles. After appropriate incubation times at 45 degrees 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 GM1 transfer to acceptors followed first-order kinetics with a half-time of about 40 h assuming that GM1 is present in equal mole fractions in the exterior and interior surfaces of the donor vesicle bilayer and that no glycolipid flip-flop occurs. GM1 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 GM1 interbilayer transfer rate included phospholipid matrix composition, initial GM1 concentration in donor vesicles, and the GM1 distribution in donor vesicles with respect to total lipid symmetry. The findings provide evidence that GM1 is molecularly dispersed at low concentrations within liquid-crystalline phospholipid bilayers.

• Research Organization: Univ. of Virginia School of Medicine, Charlottesville
• OSTI ID: 5607578
• 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
ANIMALS
BIOCHEMICAL REACTION KINETICS
BODY
BRAIN
CARBON 14 COMPOUNDS
CARBOXYLIC ACIDS
CATTLE
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
CHROMATOGRAPHY
DOMESTIC ANIMALS
ENERGY TRANSFER
ESTERS
GAS CHROMATOGRAPHY
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LIPIDS
LIPOSOMES
MAMMALS
MONOCARBOXYLIC ACIDS
NERVOUS SYSTEM
OLEIC ACID
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANOIDS
ORGANS
PHOSPHOLIPIDS
REACTION KINETICS
RUMINANTS
SEPARATION PROCESSES
TRACER TECHNIQUES
VERTEBRATES