Three-dimensional heteronuclear NMR techniques for assignment and conformational analysis using exchangeable protons in uniformly 13C-enriched oligosaccharides.
We present heteronuclear three-dimensional gradient-NMR techniques for the resonanceassignment of exchangeable (-OH and -NH) protons in uniformly 13C isotopically enrichedoligosaccharides and for the measurement of 1H-1H nuclear Overhauser enhancementsinvolving these protons. These techniques are derived from conventional HOHAHA-HSQCand NOESY(ROESY)-HSQC experiments, and are illustrated in application to a sample ofuniformly 13C-enriched Galbeta1-4GlcNAc, and demonstrate that a total of 35 ROEs involvingexchangeable protons can be detected and assigned. We present a quantitative analysis ofthese ROEs that can only be accommodated in a model of the solution behaviour of theoligosaccharide that involves considerable internal motion.
Harris
R
R
Centre for Biomolecular Sciences, University of St. Andrews, The Purdie Building, St. Andrews, KY16 9ST, U.K.
Rutherford
T J
TJ
Milton
M J
MJ
Homans
S W
SW