Glycopeptides structural analysis

V. Structural Analysis of Glycopeptides and Glycoproteins Containing Unusual... 

Multiple-ion monitoring is, however, of considerable value in structural studies, but only if model compounds of known structure are available for comparison. Such an approach has been used in the study of the carbohydrate structures of glycoproteins from different tissues.50 Separation of glycopeptides obtained from various tissues was performed on columns of concanavalin A-Sepharose. Structural analysis by multiple-ion monitoring of partially methylated, alditol acetates derived from the various fractions indicated that the glycopeptides were separated according to the linkage pattern of mannose (see Fig. 1). 

While parallel synthesis of arrays of glycopeptides is readily achieved by implementation of the building-block approach (Scheme 14.1, Strategy 2),101 glycopeptide library synthesis in a combinatorial manner via the split-mix method has yet to prove routine. The difficulty lies in the structural analysis of the vast number of compounds generated in picomolar quantities on a single bead. Whereas peptides on... 

The structural analysis of this glycopeptide sample (from asialo oxacid glycoprotein) by 500-MHz, H-n.m.r. spectroscopy, revealing a new type of microheterogeneity, gives a nice impression of the potency of this technique in detecting and identifying compounds in mixtures, even if they are present in low proportions. 

Glycoproteins constitute the most diverse of these classes of glycoconjugates. Their substructures, the glycopeptides, occur as natural and artificial degradation products of glycoproteins during metabolism and structural analysis, respectively, or they are obtained synthetically in... 

Glycomics Glycopeptides Glycoproteomics Mass spectrometry Nano liquid chromatography iV-glycans 0-glycans Profiling Structural analysis Tandem mass spectrometry... 

S. Goletz, M. Leuck, P. Franke, U. Karsten. Structure analysis of acelylated and non-acetylated O-linked MUCl-glycopeptides by post-source decay matrix-assisted laser desorption/ionization mass spectrometry. Rapid Commun. Mass Spectr. 1997,11, 1387-1398. 

Soybean 7S protein contains residues of D-mannose and 2-acetamido-2-deoxy-D-glucose. After proteolytic digestion, three related glycopeptides were isolated and structural analysis has allowed a possible structure (3) to be deduced. 

There w s, however, still a need for a close structural analysis of a mannolipid donor and the corresponding glycopeptide product in any system. 

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