High-mannose oligosaccharides from human Tamm-Horsfall glycoprotein

The present communication reports the occurrence of high-mannose oligosaccharides on Tamm-Horsfall glycoprotein prepared from human pooled urine. The Pronase digest of the glycoprotein was fractionated by gel filtration and a high-mannose glycopeptide species was separated from complex-type glycopeptides. When high-mannose glycopeptides were digested with endo--N-acetylglucosaminidase H, followed by reduction with ³H]KBH₄, three oligosaccharides were resolved by thin-layer chromatography. On the basis of chromatographic mobility and exoglycosidase digestions the composition Man₇-, Man₆-, and Man₅-GlcNAc was assigned to the three oligosaccharides. Man₆GlcNAc is by far the major component.