Ceramide glycosphingolipid synthesis from

Sphingomyelin Is Formed Directly from Ceramide Glycosphingolipid Synthesis Also Starts from Ceramide... 

Glycosphingolipid Synthesis Also Starts from Ceramide... 

Shapiro and co-workers have described [89] (in a paper submitted just before the death of this pioneer in the field of glycosphingolipid synthesis — for a review of his extensive work in this area see Ref. [1]) a synthesis of the thio-analogue (88) of glucosyl ceramide (and the saturated derivative) from 2,3,4,6-tetra-0-acetyl-l-mercapto- 3-D-glucopyranose (86) and the 1-deoxy-l-iodoceramide derivative (85) in the presence of l,8-diazabicyclo[5.4.0]undec-7-ene. The product (87) was deacylated with methano-lic barium methoxide to give (88). 

Ceramide formed in mammalian systems is metabolized to sphingomyelin, glycosphingolipids, and ceramide 1-phosphate by the actions of sphingomyelin synthase, glucosylceramide synthase, and ceramide kinase on ceramide, respectively. Ceramide synthesized in the endoplasmic reticulum is transported to the Golgi apparatus for synthesis of complex sphingolipids (93). Sphingomyelin is synthesized from ceramide by transfer of the... 

Synthesis of glycosphingolipids and sulfoglycosphin-golipids involves the addition of sugar and sulfate residues to ceramide from UDP-sugar derivatives or the activated sulfate donor 3 -phosphoadenosine-5 -phosphosulfate (Chapter 17), and appropriate transferases. These pathways are discussed in Chapter 16. Catabolism of sphingolipids is by specific lysosomal hydrolases. Several inherited disorders associated with the deficiencies of these enzymes are discussed below. 

The endoglycosidase, ceramide glycanase, is used to transfer an oligosaccharide group from a water-soluble polymer to ceramide. This enzymatic tool provides an efficient new method for polymer-supported synthesis of glycosphingolipids (119). 

New ceramide digalactosides were isolated by Hayashi s group from the marine sponge Halichondria japonica.24 To the major glycosphingolipid was assigned the structure 86, except for the stereochemistry, using FAB/MS, IR and NMR spectroscopy. The first synthesis of the ceramide 87 and therefore the structure determination were described by us.25... 

Two different glycolipid L-fucosyltransferases, involved in the biosynthesis of blood-group related glycosphingolipids, were detected in a membrane preparation isolated from a human neuroblastoma-derived clonal cell line. One catalysed the transfer of L-fucose to neolactotetraosyl- or pentaosyl-ceramide to form H-1 and B-1 glycolipids respectively. The second catalysed the transfer of L-fucose to lactotriaosylceramide to form a tetraosylceramide which was an intermediate in the synthesis of the Le -type glycolipid. 

Nishimura, S.-l. and Yamada, K. (1997) Transfer of ganglioside GM3 oligosaccharide from a water soluble polymer to ceramide by ceramide glycanase. A novel approach for the chemical-enzymatic synthesis of glycosphingolipids. J. Am. Chem. Soc. 119,10555-10556. 

---