Open AccessA 500‐MHz Proton‐Magnetic‐Resonance Study of Several Fragments of the Carbohydrate‐Protein Linkage Region Commonly Occurring in Proteoglycans
Author(s) -
HALBEEK Herman,
DORLAND Lambertus,
VELDINK Gerrit A.,
VLIEGENTHART Johannes F. G.,
GAREGG Per J.,
NORBERG Thomas,
LINDBERG Bengt
Publication year - 1982
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1982.tb06830.x
Subject(s) - linkage (software) , proton magnetic resonance , nuclear magnetic resonance , chemistry , carbohydrate , proton , biophysics , biochemistry , physics , biology , gene , nuclear physics
The proton‐magnetic‐resonance spectra of three partial structures of the carbohydrate‐protein linkage region that frequently occurs in proteoglycans, namely, β‐ d ‐Gal p ‐(1→3)‐β‐ d ‐Gal p ‐(1→4)‐β‐ d ‐Xyl p ‐(1→O)‐ l ‐Ser, were recorded in 2 H 2 O at 500 MHz; they could be completely interpreted, both for the glyco‐serines and for the corresponding glyco‐xylitols. The chemical shifts and the coupling constants were refined by computer simulation of the spectra. The change in the chemical shift of H‐4 of a d ‐galactopyranosyl residue upon substitution at C‐3 by a β‐ d ‐galactopyranosyl group is proposed to be characteristic for this particular attachment, making H‐4 of galactose a structural‐reporter group. The three constituting monosaccharides adopt the 4 C 1 ( d ) ring conformation. The terminal galactopyranosyl group and the internal galactopyranosyl residue differ as to the population of rotamers around the C‐5/C‐6 axis. Concomitantly, the flexibility of their glycosidic linkages is distinct.