A METHOD FOR REDUCTIVE CLEAVAGE OF N-GLYCOSYLAMIDE CARBOHYDRATE-PEPTIDE BOND

Article abstract of DOI:10.1016/0008-6215(88)80108-3

A new, mild method for the splitting of N-linked oligosaccharides from glycoproteins includes treatment of glycoproteins (ovomucoid, flavoprotein, ribonuclease B, hemagglutinin, or transferrin) with 2 M LiBH4 in 25 mM LiOH - 50 mM Li citrate - 70percent aqueous tert-butyl alcohol (5 h, 45 deg C), followed by hydrolysis of the resulting glycosylamine with aqueous acetic acid.The oligosaccharides formed were easily isolated by gel filtration and cation-exchange chromatography in 60-80 percent yields.The reaction was accompanied by the intense reductive cleavage of peptide bonds with formation of amino alcohols, but N-deacetylation of hexosamine was completely excluded.The optimal conditions of this reaction were chosen by use of a model glycopeptide, 2-acetamido-4-O-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-1-N-(4-L-aspartoyl)-2-deoxy-β-D-glucopyranosylamine