A novel difucosylated neutral glycosphingolipid from the eggs of the sea urchin, Hemicentrotus pulcherrimus: I. Purification and structural determination of the glycolipid.
A novel fucose-containing neutral glycosphingolipid (GL-5) was purified from the eggs of the sea urchin, Hemicentrotus pulcherrimus. The chemical structure was determined to be Fuc alpha 1-3GalNAc beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-4Glc beta 1-1Cer by methylation analysis, partial acid hydrolysis, fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The unique characteristics of GL-5 are that: the reducing terminal disaccharide portion is not Gal beta 1-4Glc but GlcNAc beta 1-4Glc; it includes a GalNAc beta 1-4GlcNAc sequence and a Fuc-GalNAc linkage; the defucosylated core is a novel trisaccharide chain; and the sugar structure is one of the smallest ever characterized for a difucosylated glycolipid. The major fatty acids were 22:1 and 22h:1, and about 30% of the total acids was 2-hydroxylated. All the long-chain bases were phytosphingosines, of which about 90% was n-t18:0. The similarity of the ceramide moiety to that of glucosylceramide from the same eggs [Kubo, H. et al. (1992) J. Biochem. 111, 726-731] suggests a close biosynthetic relationship between GL-5 and the glucosylceramide.
Kubo
H
H
Department of Life Science, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa.
Jiang
G J
GJ
Irie
A
A
Suzuki
M
M
Inagaki
F
F
Hoshi
M
M
D000818:Animals; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000032:analysis; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D005227:Fatty Acids / Q000032:analysis; D005643:Fucose; D006028:Glycosphingolipids / Q000737:chemistry* / Q000302:isolation & purification; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008969:Molecular Sequence Data; D010063:Ovum / Q000737:chemistry*; D012617:Sea Urchins; D016339:Spectrometry, Mass, Fast Atom Bombardment
D002241:Carbohydrates; D005227:Fatty Acids; D006028:Glycosphingolipids; D005643:Fucose