Periodate oxidation labeled sugars

Figure 9.48 A cyanine dye containing a hydrazide group can be used to label glycans at their reducing end or other reducing sugars, forming a hydrazone linkage. Glycoproteins also can be labeled after periodate oxidation to form aldehyde groups.

The following protocol describes the use of biotin-hydrazide to label glycosylated proteins at their carbohydrate residues. Control of the periodate oxidation level can result in specific labeling of sialic acid groups or general sugar residues (Chapter 1, Section 4.4). 

In addition to the foregoing examples, periodate oxidation has been applied to isotopically labeled sugars (for the determination of label distribution), 226 -226 to certain branched-chain sugars,227-229 and to some nitrogenous derivatives of the simple sugars.230-236... 

Sometimes, the most convenient method of preparation of the labeled sugar required is by chemical or enzymic modification of a more readily available, or commercially available, sugar. Thus, D-ribose-3-t has been prepared from l,2 5,6-di-0-isopropylidene-a-D-allofuranose-3-t by way of 1,2-O-isopropylidene-a-D-allofuranose-3-t, followed by periodate oxidation, and reduction.52... 

The increased sensitivity of the sialic acid glycerol moiety to periodate oxidation as compared with other sugars has been used as a coupling method to label gangliosides selectively (141). 

NADP+ containing an acyclic 2, 3 - dialdehyde nicotinamide sugar moiety (3) can be synthesized hy periodate oxidation (43) and exists primarily as the hydrated gem-diol. This analog has been used as an affinity label [it inactivates glucose-6-phosphate dehydrogenase (44)], and is active with some dehydrogenases (45). 

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