N Acetylglucosamine

Fig. 2. Generalized structure of N-linked oligosaccharide of the pituitary glycoprotein hormones. SO = sulfate, GIcNAc = N — acetylglucosamine, GalNAc = N — acetylgalactosamine, Man = mannose, Fuc = fucose, SA = sialic (neuraminic) acid.

Disorders caused by mislocalization of lysosomal proteins (e.g., mutations in the N-acetylglucosamine 1-phosphotransferase leading to inclusion cell disease). 

Acetyl hexosamines N-Acetylglucosamine (GIcNAc) N-Acetylgalactosamine (GalNAc)... 

Figure 20-7. Summary of the interrelationships in metabolism of amino sugars. (At asterisk Analogous to UDPGIc.) Other purine or pyrimidine nucleotides may be similarly linked to sugars or amino sugars. Examples are thymidine diphosphate (TDP)-glucosamine and TDP-N-acetylglucosamine.

Figure 20 Post-column detection of mono- and disaccharides with 4-amino-benzoylbenzamide. Column CarboPac PA-1. Gradient 1-10 mm NaOH (0-20 min.), 10-20 mM NaOH (20-35 min). Flow rate 1 ml/min. Detection absorbance at 400 nm after reaction with 4-aminobenzoylhydrazide. (a) Standard mixture of fucose (1), arabinose (2), galactose (3), glucose (4), xylose and N-acetylglucosamine (5 and 6), allose (7), 3-fucosyllactose (8), fructose (9), lactose (10), Man-(3-(l,4)-GlcNac. (b) Normal urine, (c) Urine from a child with (3-mannosidosis. (Reproduced with permission of Academic Press from Peelen, G. O. H., de Jong, J. G. N., and Wever, R. A., Anal. Biochem., 198, 334, 1991.)...

The equivalent of the tryptic fragment of human transferrin receptor has been expressed in Chinese hamster ovary cells and its structure determined at a resolution of 0.32 nm (Lawrence et ah, 1999). The asymmetric unit of the crystals contains four transferrin receptor dimers. Interpretable electron density is found for the entire tryptic fragment except for Arg-121 at the amino terminus, and density is also seen for the first N-acetylglucosamine residue at each of the N-glycosylation sites. The transferrin receptor monomer is made up of three distinct domains, organized such that the dimer is butterfly shaped (Figure 5.10, Plate 7). The likely orientation of the dimer with respect to the plasma membrane has been assigned on the basis of the... 

Initially, a 14-sugar oligosaccharide containing N-acetylglucosamine, mannose and glucose, known as the precursor oligosaccharide, is added en bloc to the side... 

Stable and potent P2Y2 receptor agonists are being administered by inhalation as a potential treatment for cystic fibrosis. P2YH receptors are unusual in that they are activated by UDP-glucose, UDP galactose and UDP-N-acetylglucosamine [22],... 

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