Mannose chromatography

The compositions of high-mannose oligosaccharides isolated from urine of animals suffering from genetic or chemically induced mannosidoses have been assigned from their f.a.b.-mass spectra. After chromatography, some samples were sufficiently pure to be examined underivatized. Others required conversion into their peracetylated derivatives. 

Townsend, R. R., Atkinson, R H., and Trimble, R. B., Separation of high-mannose isomers from yeast and mammalian sources using high pH anion-exchange chromatography, Carb. Res., 215, 211. 1991. 

TES-45 and TES-55 are two glycoproteins that have yet to be identified at a genetic level, but evidence has been obtained that they may also be lectins. Carbohydrate affinity chromatography with mannose-agarose shows that TES-32 selectively binds as expected, but that TES-45 is also present in small amounts (Loukas et al., 1999) unlike TES-32, TES-45 does not bind to A -ace Lylgalac t< isamine. No sequence information has yet been obtained on TES-45, but it is recognized by polyclonal antibodies generated to TES-32,... 

To facilitate parallel synthesis and purification of triazolyl derivatives of sugars, the products are tagged with an azulene chromophore. For this purpose, guajazulene, an inexpensive azulene, is converted to propargylic ester 1094 and reacted with mannose derivative 1095 to provide a mixture of regioisomers 1096 (44%) and 1097 (32%). Separation of the products can be easily achieved by chromatography because they are visible on the column (Scheme 181) <2006EJ01103>. 

Bedair, M., and El Rassl, Z. (2004). Affinity chromatography with monolithic capillary columns I. Polymethacrylate monoliths with Immobilized mannan for the separation of mannose-binding proteins by capillary electrochromatography and nano-scale liquid chromatography. /. Chromatogr. A 1044, 177-186. 

Figure 13.19 Affinity chromatography with 2,2,6,6-tetiamethylpiperidine A-oxide (TEMPO)-/ mannose-functionalized dendrimers. Electron paramagnetic resonance spectra for one TEMPO/mannose experiment are shown.

Analysis of glycosaminoglycan hydrolyzates is often complicated by the presence of basic and acidic glycoses, in addition to neutral monosaccharides. Adsorption chromatography on silica gel was used to classify such a hydrolyzate, and the neutral fraction was shown to contain D-glucose, D-galactose, and D-mannose.288 Separation on ion-exchange resins may also be used.51,149 The resolution of the acidic and basic fractions is discussed in Sections IX (p. 71) and X (p. 78). 

Yamashina and coworkers18 72 isolated, on Dowex 50, the total aspartamidoglycan from a proteolytic digest of ovalbumin. It had mean D-mannose hexosamine L-asparagine ratios of 5 3 1. Purified a-D-mannosidase liberated exactly half the D-mannose from the glycopeptide. The residue was subjected to chromatography on Bio-Gel... 

These fractions, altogether, account for only 30% of the mannose in the ovalbumin digest before separation by ion-exchange chromatography. 

Thin-layer chromatography of 2-acylamido-2-deoxy-D-mannoses resulting from cleavage of sialic acids with acylneuraininate pyruvate-lyase is described in Ref. 107, together with the RF values of the different 0-acyl-2-acylamido-2-deoxy-D-mannose species. 

Lee, Acree, and Shallenberger have in some cases carried out actual isolations of the anomeric trimethylsilyl per-O-trimethylsilyl glycosides by preparative gas chromatography and have then characterized the separated derivatives by optical rotation, elementary analysis, and NMR spectroscopy (30). These characterizations, which have been done for glucose, mannose, and galactose (see below) confirm the usefulness of the GLC technique. 

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