Glycosyltransferases donor

W. R. Figures and J. R. Edwards, a-D-Glucopyranosyl fluoride as a D-glucopyr-anosyl donor for a glycosyltransferase complex from Streptococcus mutans FA1, Carbohydr. Res., 48 (1976) 245-253. 

The general term UDP-glycosyltransferase or the more specific ones UDP-glucuronyl-, UDP-glucosyl-, and UDP-xylosyltransferase will bo employed as convenient. They are used primarily to denote enzyme activities observable in broken cell preparations. This practice does not imply any expression of opinion with regard to the existence of either a single polyfunctional enzyme system, or of several enzymes with different specificities toward the sugar donor (Section 7). 

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... 

Polyprenyl glycosyl monophosphates have been shown to serve as glycosyl donors in the biosynthesis of side chains of some polysaccharides. Contrary to glycosyl nucleotides, they represent membrane-bound glycosyl donors which may be preferable for some glycosyltransferases. 

As already mentioned, formation of glycosidic linkages between monomeric units of the carbohydrate-containing polymers of the bacterial cell-surface is catalyzed by membrane-bound glycosyltransferases, and glycosyl nucleotides are the usual glycosyl donors in the reaction. 

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