2-Acetamido-2-deoxy-galactose

The D-galactosyl residues are the same as in disaccharide 33, and the fact that ribitol is substituted at 0-2 was evident from the methyl-ation analysis. Finally, a nonreducing tetrasaccharide was obtained, containing D-galactose, 2-acetamido-2-deoxy-D-galactose, and ribitol residues in the proportions 2 1 1. From these results, and periodate-oxidation studies, structure 36 was proposed for the neutral hexa-saccharide. 

Origin of glycans Galactose 2-Acetamido-2-deoxy galactose References... 

On methylation, with subsequent hydrolysis, tetrasaccharide 83 gives 2,3,6-tri-O-methyl-D-glucose, 2,4,6-tri-O-methyl-D-galactose, 2-acetamido-2-deoxy-3,6-di-0-methyl-D-glucose, and 2,3,4,6-tetra-O-methyl-D-galactose. 

A mucin isolated from rat tracheal transplants contained protein (16.5%) and had D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, and neuraminic acid as the principal sugars.The presence of O-glycosidic linkages was established by 3-elimination in alkaline borohydride solution. 

A specific interaction was observed between the ganglioside (1), which had been incorporated in glycerol monoleate planar bilayer membranes, and folli-tropin. A five-fold increase in conductance was measured in the presence of (1) while neither di- or tri-sialogangliosides showed any effect. The increase was suppressed by the presence of an equimolar mixture of D-galactose, 2-acetamido-2-deoxy-D-galactose, and iV-acetylneuraminic acid. The results favour the hypothesis that gangliosides may contribute to the formation of functional glycoprotein receptors. 

A-Acetylneuraminic acid was shown to be a component of the lipopoly-saccharide of Salmonella touera along with residues of D-glucose, D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-keto-3-deoxyoctonate, and an unidentified amino sugar. 

Specifically the 4-deoxyhexosyl disaccharide (50) has been repeated and structurally characterised by X-ray diffraction, and the following 6-deoxyhexosyl compounds have been prepared 2-Q-a-L-fucopyranosyl-D-galactose,2-acetamido-2-deoxy-(3- and 4-Q-a-L-fucopyranosyl)-D-glucose as their trifluoroacetamidopropyl p-glycosides,methyl 3[3-(2-Q-a-L-rhainnopyranosyl-a-L-rhamnopyranosyloxy)decanoyloxy] decanoate (51, the rhamnolipid of Pseudomonas aeruginosa >. and methyl 3-Q-(L-rhamnopyranosyl)-i8-D-... 

Sheares, B.T. and Carlson, D M. Two distinct UDP-galactose 2-acetamido-2-deoxy-D-glucose 4 P-galactosyltransferases in porcine trachea. J. Biol. Chem. 1984, 259, 8045-8047. 

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