Glycosphingolipids glycosyltransferases

Glycosphingolipid Glycosyltransferase Assays. A 25-33% (vol/vol) homogenate of mouse tumors or harvested cells in 0.32 M sucrose containing 0.1% 2-mer-captoethanol and 0.001 M EDTA (pH 7.0) was used as enzyme source. Membrane fractions for glycolipid gly-cosyltransferase assays were isolated at the junction of 0.32 M and 1.2 M on a discontinuous sucrose density gradient (32,43). 

Basu, S, Basu, M, Expression of glycosphingolipid glycosyltransferases in development and transformation, Glycoconjugates, 3, 265-285, 1982. 

Keenan, T. W., Morre, D. J., and Basu, S., 1974, Ganglioside biosynthesis. Concentration of glycosphingolipid glycosyltransferases in Golgi apparatus from rat liver, /. Biol Chem. 249 310. 

The incubation mixture for the biosynthesis of glycosphingolipids usually includes an enzyme preparation, a glycosyl donor, a glycolipid acceptor, a detergent, and metal ions. Most of the glycosyltransferases are membrane bound and are usually associated with the microsomal... 

Glycosphingolipid Ganglioside Biosynthesis Catabolism Nervous system Endoplasmic reticulum Golgi Glycosyltransferase Glycosidase Lipid-storage disorder... 

Figure 5 Pathways of biosynthesis of the GSL. Glycosyltransferases in the ER sequentially add sugars to produce the various glycolipids. Gangliosides (i.e., glycosphingolipids containing sialic acid) are produced by the addition of NANA to lactosyi-ceramide to form Gmi, which can then be further glycosylated to Gm2 and then Gms- Globosides also come from lactosyi-ceramide by addition of another Gal and then a GalNAc.

Fig. 9. Combinatorial nature of glycosphingolipid biosynthesis (modified from T. Kolter and K. Sandhoff, 2002). Glycosphingolipids are shown using symbols from Fig. 8. SAT refers to sialyltransferase and GalNAcT and GalT to glycosyltransferases for UDP-GalNAc and UDP-Gal, respectively.

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