a carbohydrate composed of three to ten sugar molecules is called saccharide.
a carbohydrate composed of three to ten sugar molecules is called saccharide.
a carbohydrate composed of three to ten sugar molecules is called a(n)?
saccharide
to act as glycosyl donors, those monosaccharides should exist in a highly energetic form. this occurs as a result of a reaction between nucleoside triphosphate (ntp) and glycosyl monophosphate (phosphate at anomeric carbon). the recent discovery of the reversibility of many glycosyltransferase-catalyzed reactions calls into question the designation of sugar nucleotides as 'activated' donors.









































section::::types.









































there are ten sugar nucleotides in humans which act as glycosyl donors and they can be classified depending on the type of the nucleoside forming them:









































bullet::::- uridine diphosphate: udp-α-d-glc, udp-α-d-gal, udp-α-d-galnac, udp-α-d-glcnac, udp-α-d-glca, udp-α-d-xyl









































bullet::::- guanine diphosphate: gdp-α-d-man, gdp-β-l-fuc.
nucleotide sugar
the process of n-linked glycosylation starts with the formation of dolichol-linked glcnac sugar. dolichol is a lipid molecule composed of repeating isoprene units. this molecule is found attached to the membrane of the er. sugar molecules are attached to the dolichol through a pyrophosphate linkage (one phosphate was originally linked to dolichol, and the second phosphate came from the nucleotide sugar). the oligosaccharide chain is then extended through the addition of various sugar molecules in a step-wise manner to form a precursor oligosaccharide.
n-linked glycosylation