Novel specificities of Mucor hiemalis endo-beta-N-acetylglucosaminidase acting complex asparagine-linked oligosaccharides.
Mucor hiemalis endo-beta-N-acetylglucosaminidase (Endo-M) was proved to act on complex type biantennary oligosaccharides of glycoproteins by using dansylated asparagine-linked and pyridylaminated oligosaccharides, as the substrate. The enzyme could act on both asialo- and sialo-biantennary oligosaccharides. This is the only endo-beta-N-acetylglucosaminidase known to act on sialo glycans, though their activity for them was weak. The enzyme could liberate complex type biantennary oligosaccharides from native human asialotransferrin, which was ascertained by a combination of the pyridylaminated method and HPLC. The enzyme had substrate specificity for high-mannose type oligosaccharides different from those of the endo-beta-N-acetylglucosaminidases of other microorganisms: ovalbumin glycopeptide-IV was a better substrate for Endo-M than glycopeptide-V. The enzyme could act on complex type triantennary oligosaccharides of dansylated glycopeptide prepared from calf fetuin. The enzyme had various novel specificities in regard to activities on complex type and high-mannose type oligosaccharides in glycoproteins.
Yamamoto
K
K
Department of Food Science and Technology, Faculty of Agriculture, Kyoto University, Japan.
Kadowaki
S
S
Fujisaki
M
M
Kumagai
H
H
Tochikura
T
T
D001212:Asialoglycoproteins / Q000378:metabolism; D001216:Asparagine / Q000737:chemistry*; D002240:Carbohydrate Sequence; D006020:Glycopeptides / Q000378:metabolism; D006868:Hydrolysis; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D009089:Mucor / Q000201:enzymology*; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism*; D013379:Substrate Specificity; D014168:Transferrin / Q000031:analogs & derivatives / Q000378:metabolism; D000509:alpha-Fetoproteins / Q000378:metabolism
D001212:Asialoglycoproteins; D006020:Glycopeptides; D009844:Oligosaccharides; D014168:Transferrin; D000509:alpha-Fetoproteins; C017031:asialotransferrins; D001216:Asparagine; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase