Open AccessStructure of Glycopeptides Isolated from Bovine Milk Component PP3
Author(s) -
Girardet JeanMichel,
Coddeville Bernadette,
Plancke Yves,
Strecker Gérard,
Campagna Sylvie,
Spik Geneviève,
Linden Guy
Publication year - 1995
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1995.939_a.x
Subject(s) - glycopeptide , chemistry , glycan , peptide , chromatography , mass spectrometry , bovine milk , biochemistry , pronase , glycoconjugate , glycoprotein , trypsin , enzyme , antibiotics
The heat‐stable acid‐soluble phosphoglycoprotein component PP3 was isolated from the bovine milk proteose peptone fraction by concanavalin A affinity chromatography. Glycopeptides were released by pronase digestion of the milk component PP3 and were subsequently separated by high‐pH anion‐ex‐change chromatography on Carbopac PA‐1. The primary structures of the glycan and peptide moieties of eight N‐glycopeptides have been established by combining methylation analysis, mass spectrometry, 400‐MHz 1 H‐NMR spectroscopy, and peptide sequence analysis. All the analyzed fractions contained biantennary N ‐acetyllactosamine‐type carbohydrate chains, some of them with a GalNAc(β1–4)GlcNAc or a NeuAc(α2–6)GalNAc(β1–4)GlcNAc group. This particular sequence did or did not replace the Gal(β–4)GlcNAc group usually found in most N‐linked glycans. Moreover, the sialylated Gal and GalNAc residues were only found on the Man(α1–3) antenna.