Structure Determination by Mass Spectrometry

A-glycans in vertebrates exist as high-mannose, hybrid, or complex types (Fig. 3). The high-mannose type is defined as glycans with only mannose residues as terminal elaboration, based on the core structure. Hybrid glycans contain both 

The biosynthetic pathway of A-linked glycans has been defined by the extensive research efforts of multiple groups, and summaries of the present understanding of the process are now readily available. The pathway for biosynthesis of A-linked glycans includes three major steps. 

The complex mechanism of glycan synthesis is a factor that contributes to the difficulty of studying glycan structures, but recent advances in mass spectrometry (MS) technologies have made it possible to determine a growing number of glycan structures experimentally. 

Protein glycosylation depends on the overall protein conformation, the effect of 

Throughout its various applications, all MS is based on the measurement of the miz ratios of charged particles in a vacuum. In order to measure the miz ratio of samples, all mass spectrometers contain three main components ionization source, mass analyzer, and ion detector. 

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An example of how information from fragmentation patterns can be used to solve structural problems is given in Worked Example 12.1. This example is a simple one, but the principles used are broadly applicable for organic structure determination by mass spectrometry. We ll see in the next section and in later chapters that specific functional groups, such as alcohols, ketones, aldehydes, and amines, show specific kinds of mass spectral fragmentations that can be interpreted to provide structural information. 

Dell A. and Morris H.R. (2001), Glycoprotein structure determination by mass spectrometry, Science 291, 2351-2356. 

Biemaim, K. Four Decades of Structure Determination by Mass Spectrometry From Alkaloids to Heparin. J. Am. Chem. Soc. Mass Spectrom. 2002, 73, 1254-1272. 

This substance represents the largest biomolecule structurally determined by mass spectrometry thus far. 

The feasibility of structural determination by mass spectrometry was demonstrated with integerrine of which only 5.5 mg was available (34a). 

Morris, H. R. (1980). Biomolecular structure determination by mass spectrometry. Nature (London) 286, 447-452. 

Anne Dell, Howard R. Morris, Glycoprotein Structure Determination by Mass Spectrometry, Science, 291 (2001), 2351-2356. 

Biemann, K. Four decades of structure determination by mass spectrometry from alkaloids to heparin. 

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