Characterization of neutral glycosphingolipids in human cataractous lens.
Neutral glycosphingolipids were purified from human senile cataractous lenses by a combination of solvent extraction, Folch's partition, acetylation, and column chromatography using DEAE-Sephadex and Iatrobeads. Six major glycosphingolipids (A-F) from monohexosylceramide to pentahexosylceramide were identified by sugar composition analysis, methylation analysis, secondary ion-mass spectrometry, glycosidase digestion, and chromium trioxide oxidation. Their structures suggested that they were closely related in their metabolism: their sugar chains were in sequence and their ceramide moieties were similarly composed, namely C16:0 and C24:1 constituted most of the fatty acids, and long-chain base components were mostly C18-dihydrosphingosine with a small portion of C18-sphingosine. The sugar chains implied two pathways branching from lactosylceramide: one to globotriaosylceramide and the other to lactotriaosylceramide, which leads to the production of Le(x) glycolipid via neolacto type 2 core chain.
Department of Physiology, Toho University School of Medicine, Tokyo, Japan.
M
M
Ogiso
A
A
Irie
H
H
Kubo
M
M
Komoto
T
T
Matsuno
Y
Y
Koide
M
M
Hoshi
D000595:Amino Acid Sequence; D002240:Carbohydrate Sequence; D002386:Cataract / Q000378:metabolism*; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D006028:Glycosphingolipids / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D007908:Lens, Crystalline / Q000378:metabolism* / Q000473:pathology; D013058:Mass Spectrometry; D008745:Methylation; D008969:Molecular Sequence Data
D006028:Glycosphingolipids