Solution conformations of GM3 gangliosides containing different sialic acid residues as revealed by NOE-based distance mapping, molecular mechanics, and molecular dynamics calculations.
The conformation of the GM3 ganglioside, Neu5Ac alpha 2-3Gal beta 1-4Glc beta 1-1 Cer, and its analogs containing the Neu5Gc or Neu4Ac5Gc residues (Gc = glycolyl, CH2OHCO) was investigated in Me2SO-d6 solution with the aid of a distance-mapping procedure based on rotating-frame NOE contacts, with hydroxyl protons being used as long-range sensors defining the distance constraints. A pronounced flexibility found for both the Neu-Gal and Gal-Glc linkages was confirmed by 1000-ps molecular dynamics simulations. Similar results, although based on a smaller number of NOE constraints, were obtained for GM3 gangliosides anchored in mixed D2O/dodecylphosphocholine-d38 micelles and for the Neu5Ac-, Neu5Gc-, and Neu5,9Ac2-sialyllactoses dissolved in D2O. No noteworthy differences in conformational behavior of the glycan chains of the three gangliosides or sialyllactoses were observed in either of the media.
Siebert
H C
HC
Max-Planck-Institut für Medizinische Forschung, Heidelberg, Germany.
Reuter
G
G
Schauer
R
R
von der Lieth
C W
CW
Dabrowski
J
J
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005679:G(M3) Ganglioside / Q000032:analysis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid; D051381:Rats; D012794:Sialic Acids / Q000032:analysis*; D012996:Solutions
D005679:G(M3) Ganglioside; D012794:Sialic Acids; D012996:Solutions; D019158:N-Acetylneuraminic Acid