BRAIN-TYPE N-GLYCOSYLATION OF ASIALO-TRANSFERRIN FROM HUMAN CEREBROSPINAL-FLUID

Asialo-transferrin from human cerebrospinal fluid was purified to homo geneity, Investigation of the structural characteristics of its oligos accharides support our hypothesis of 'brain-type' glycosylation of int rathecally synthesized cerebrospinal fluid proteins, For carbohydrate structural analysis, high-pH anion-exchange chromatography, methylatio n analysis, liquid secondary ion- and matrix-assisted laser desorption / ionization mass spectrometry of the permethylated derivatives were u sed, The major structure turned out to be a complex-type agalactodiant ennary oligosaccharide with bisecting N-acetylglucosamine and proximal fucose, Analysis of a second transferrin preparation containing both asialo- and sialo-transferrin revealed another major glycan species de rived from the sialylated transferrin variant which is galactosylated and lacks bisecting N-acetylglucosamine and fucose.