N-Glycoprotein

Kerekgyarto, J. Vanderven, J. G. M. Kamerhng, J. P. Liptak, A. Vliegenthart, J. F. G., Synthesis of a Selectively Protected Trisaccharide Building Block That Is Part of Xylose-Containing Carbohydrate Chains from N-Glycoproteins. Carbohydr. Res. 

Otvos Jr. L, Urge L, Hollosi M, Wroblewsky K et al., Automated solid-phase synthesis of glycopeptides, Incorporation of unprotected mono- and disaccharide units of N-glycoprotein Antennae into T cell epitopic peptides, Tetrahedron Letters, 31 5889-92, 1993. 

The application of electron-impact mass spectrometry (e.i.m.s.) to carbohydrate compounds has been discussed in this Series by Kochetkov and Chizhov. The presence of the 2-acetamido-N-(L-aspart-4-oyl)-2-deoxy-)3-D-glucopyranosylamine (11), carbohydrate-peptide linkage in N-glycoproteins was demonstrated by e.i.m.s. The fragmentation patterns of synthetic glycopeptides containing an N-(L-aspart-4-oyl)glyco-... 

A-Acetylneuramic acid (D-NeupAc, NN) H HO ho h 3C0CHN OH N-Acetylneuramic acid, NeuAc is 5-acetamido-3,5-dideoxy-D-glycero-D-galacto-non-2-ulosonic acid. Substituted neuramic acids are also designated as sialic acid (Sia). Sia is linked to oligosaccharide chain of N-glycoprotein via a-2—>3 and a-2 6. 

Unverzagt C, Kajihara Y (2013) Chemical assembly of N-glycoproteins a refined toolbox to address a ubiquitous posttranslational modification. Chem Soc Rev 42 4408-4420... 

A review of the isolation and separation of phosphatldes and glyco-lipids, by solvent fractionation, preparative column chromatography, and h.p.l.c., has appeared. Lipid X (16) and Lipid Y (17)> rel-ated to lipid A and found in E. coli mutants, have been synthesized. Biologically active monosaccharide Lipid A analogues (18) have been synthesized from the appropriate I -substituted butyl glucosaminide. Reference is made to tri- and tetrasaccharide pyrophosphate esters, intermediates in N-glycoprotein biosynthesis. 

A combination of n.m.r. spectroscopy and theoretical calculations was employed in conformational studies on the pentasaccharide (46) which represents the binding site of antithrombin on xylose-containing oligosaccharides, such as the tetrasaccharide (47), related to N-glycoproteins, and on the branched trisaccharides (48) for each of which a highly predominant (>90%) conformer was detected. 

Cacan R, Duvet S, Kmiecik D, Labiau O, Mir AM, et al. Glyco-deglyco processes during the synthesis of N-glycoproteins. Biochimie 1998 50 59-68. 

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