Monosaccharides in glycoproteins

SOGA, T., HEIGER, D.N., Simultaneous determination of monosaccharides in glycoproteins by capillary electrophoresis, Anal. Chem., 1998,261, 73-83. 

Anumula KR (1994) Quantitative determination of monosaccharides in glycoproteins by high-performance liquid chromatography with highly sensitive fluorescence detection. Analytical Biochemistry 220 275-283. 

Kwon H and Kim J (1993) Determination of monosaccharides in glycoproteins by reverse-phase high-performance liquid chromatography. Analytical Biochemistry 215 243-252. 

Source From Simultaneous determination of monosaccharides in glycoproteins hy capillary electrophoresis, in Anal. Biochem. " ... 

A-acetyl-mannosamine is an important precursor for the biosynthesis of the nine carbon sugar acid, iV-acetyl-D-neuraminic acid (see section 10.5 and Fig. 10.8A) that is frequently found as a monosaccharide in glycoproteins and glyco-lipids (see Chapter 9). 

Ijiri, S. Todoroki, K. Yoshida, H. Yoshitake, T. Nohta, H. Yamaguchi, M. Sensitive determination of rhodamine 110-labeled monosaccharides in glycoprotein by capillary electrophoresis with laser-induced fluorescence detection. J. Chromatogr., A 2010,1217, 3161-3166. 

Figure 9.12 Deoxy derivatives. These contain one less oxygen atom than the monosaccharide from which they are derived. 2-Deoxyribose is a most important deoxy pentose and is a major constituent of deoxyribonucleic acid (DNA). Deoxy hexoses are widely distributed among plants, animals and microorganisms especially as components of complex polysaccharides. Examples are rhamnose (6-deoxymannose), a component of bacterial cell walls, and fucose (6-deoxygalactose), which is often found in glycoproteins and is an important constituent of human blood group substances.

Chaplin used methanolysis for the analysis of carbohydrates in glycoproteins. His method was a variation of the foregoing procedures, with an improvement of using tert-hvAyX alcohol to remove hydrogen chloride by coevaporation, instead of prolonged trituration with silver carbonate. His method is useful for samples containing uronic acids and lipids. Mononen studied methanolysis, followed by deamination and reduction with borohydride, for determination of the monosaccharide constituents of glycoconjugates. This method was applied to a lipid-free, protein fraction of rat brain. 

G. Legler Basic monosaccharide derivatives tools for exploring the active site of glycohydrolases and for studies in glycoprotein biosynthesis T. Suami Synthetic ventures in pseudo-sugar chemistry S. David Immobilized enzymes in preparative carbohydrate chemistry... 

To analyze potential interference of amino acids in monosaccharide analysis, each of the 20 amino acids (10 /xg each, each injected separately) was subjected to the chromatography conditions used for separating, detecting, and quantifying monosaccharides. In addition to PAD detection, we monitored UV detection at 215 nm after the electrochemical detector to verify amino acid electrochemical detection. Ten amino acids (R, K, Q, V, N, A, I, L, T and C) eluted between 2 and 25 min and were both PAD and UV active. Of these ten, two amino acids could potentially interfere with monosaccharide analysis. Glutamine was found to elute as a shoulder on mannose. However, acid hydrolysis conditions used to release monosaccharides from glycoproteins likely would oxidize glutamine. 

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