Glycosphingolipid composition of human semen.
Glycosphingolipids were extracted from human semen and purified. Based on the fluorometric assay of sphingosine, in spermatozoa a content of 4.4 +/- 0.9 nmol/10(8) cells of gangliosides and 22.1 +/- 1.7 nmol/10(8) cells of neutral glycosphingolipids was determined. Seminal plasma contained 4.1 +/- 0.6 nmol gangliosides and 29.3 +/- 1.5 nmol neutral glycosphingolipids per milliliter. The glycosphingolipid component patterns of human spermatozoa and seminal plasma were determined by thin-layer chromatography. Four neutral glycolipids were isolated and their carbohydrate moieties were characterized. All of these glycolipid components belonged to the globo-series. Gas chromatography, combined gas chromatography/mass fragmentography, and exoglycosidase treatments revealed the following structures for the glycosphingolipids of human semen: Glc1-Cer, Gal beta 1-4Glc1-Cer, Gal alpha 1-4Gal beta 1-4Glc1-Cer, and Gal-NAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc1-Cer. In addition, the occurrence of trace amounts of lactoneotetraosyl- and lactoneohexaosylceramide was detected by immunostaining after thin-layer chromatographic separation. Human spermatozoa, as well as seminal plasma, contained the gangliosides Glac1,Glac2, a sialolactoneotetraosylceramide, and a sialolactoneohexaosylceramide. The gangliosides were identified on the basis of their running characteristics by high-performance thin-layer chromatography, exoglycosidase treatment, and immunostaining after thin-layer chromatography. The ceramide composition of the glycolipids in human spermatozoa, as well as in seminal plasma, was dominated by C22:0-behenic acid and the saturated sphingoid d18:0, sphinganine.
Ritter
G
G
Physiologisch-Chemisches Institut, Philipps-Universität Marburg, Federal Republic of Germany.
Krause
W
W
Geyer
R
R
Stirm
S
S
Wiegandt
H
H
D002852:Chromatography, Ion Exchange; D002855:Chromatography, Thin Layer; D005732:Gangliosides / Q000302:isolation & purification; D006026:Glycoside Hydrolases; D006028:Glycosphingolipids / Q000032:analysis*; D006801:Humans; D008297:Male; D012661:Semen / Q000032:analysis*; D013094:Spermatozoa / Q000032:analysis*
D005732:Gangliosides; D006028:Glycosphingolipids; D006026:Glycoside Hydrolases