Glycoconjugates enzymic analysis

Gershoni, J.M., Bayer, E.A., and Wilchek, M. (1985) Blot analysis of glycoconjugates Enzyme-hydrazide— A novel reagent for the detection of aldehydes. Anal. Biochem. 146, 59-63. 

Of the many areas where these methods have been useful, the greatest impact has been in the area of complex plant and animal oligosaccharides, glycopeptides, and other glycoconjugates (see Table IV). The isolation of these pure carbohydrates, by the methods described, has allowed their spectroscopic, chemical, and enzymic analysis, in many cases for the first time (see Addendum). 

The first four chapters deal with different aspects of carbohydrate chemistry. In Chapter 1, Derek Horton discusses the development of carbohydrate chemistry and biology from antiquity to the present and beyond and summarizes the structures and methods for structural analysis of complex carbohydrates. In Chapter 2, Bo Xie and Catherine Costello review the state-of-art application of mass spectrometry to the structural analysis of complex carbohydrates. In Chapter 3, Zhongwu Guo briefly summarizes the types of glycosylation methods and synthetic strategies that are commonly used in the chemical synthesis of glycoconjugates. Enzymes have simplified the synthesis of some oligosaccharides, and in Chapter 4,... 

Recent applications of HPAEC-PAD are many and varied. A representative list includes quantitation of polyglucose metabolites in plasma of dialysis patients,148 analysis of heat-treated milk,149 carbohydrate content in lipopolysaccharides,150 phosphorylated sugars in tissue samples,151 composition of soybean meal,152 carbohydrate composition of recombinant modified tissue plasminogen activator,153 analysis of cyclization products from an enzyme reaction,154 carbohydrate content of glycoconjugate vaccines,155 and monitoring of patients with rheumatoid arthritis.156... 

It has been mentioned in section 5.3.2 and refs. [11,12] that the commercially available sialate lyase is an excellent tool for the analysis, e.g. by HPLC or GLC, of a substance suspected to be a sialic acid. The enzyme has also proved to be useful in clinical determinations of these monosaccharides [900,901]. For the analysis of glycoconjugate-bound sialic acids, e.g. in the bloodstream, a combination with sialidase treatment is necessary. 

Reversed Hydrolysis vs. Transglycosylation. Glycosidases have been used for several years for the selective hydrolysis of carbohydrates, such as for the hydrolysis of starch and for the analysis of glycoconjugate carbohydrate structures. These enzymes also can be used for the regioselective and stereospecific synthesis of oligosaccharides in equilibrium-controlled (reversed-hydrolysis. Equation 1) or kinetically controlled (transglycosylation. Equation 2) reactions ... 

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