title: New evidence of the substrate specificity of endo-beta-N-acetylglucosaminidase D.
abstract: The susceptibility of a variety of oligosaccharides to endo-beta-N-acetylglucosaminidase D was investigated. The oligosaccharides having the structures of Man alpha 1----6 (GlcNAc beta 1----4Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4(+/- Fuc alpha 1----6)GlcNAcOT, derived from complex type triantennary sugar chains, released +/- Fuc alpha 1----6GlcNAcOT upon incubation with the enzyme at almost the same rate as Man alpha 1----6(Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4GlcNAcOT. When the reaction products were reduced with NaB3H4 and analyzed by Bio-Gel P-4 column chromatography, a new radioactive peak was detected in both cases. This new radioactive oligosaccharide was confirmed to be Man alpha 1----6(GlcNAc beta 1----4Man alpha 1----3)Man beta 1----4GlcNAcOT in the former case and Man alpha 1----6(Man alpha 1----3)Man beta 1----4GlcNAcOT in the latter. These results indicated that endo-beta-N-acetylglucosaminidase D does not require the presence of a free hydroxyl group at the C-4 position of the alpha-mannosyl residue of the trisaccharide glycon: Man alpha 1----3Man beta 1----4GlcNAc beta 1----.
mesh_terms: D000118:Acetylglucosaminidase / Q000378:metabolism*; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D006026:Glycoside Hydrolases / Q000378:metabolism; D006596:Hexosaminidases / Q000378:metabolism*; D007700:Kinetics; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D009844:Oligosaccharides; D013296:Streptococcus pneumoniae / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D009844:Oligosaccharides; D006026:Glycoside Hydrolases; D006596:Hexosaminidases; D000118:Acetylglucosaminidase; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase