A comparison of the conformation of sucrose octasulfate, free and bound to acidic fibroblast growth factor.
The conformation of sucrose octasulfate free in solution has been determined based on high-resolution NMR spectroscopy. Three-bond 1H-1H scalar coupling constants, laboratory and rotating frame NOEs, long-range 1H-13C scalar coupling constants, and chemical-shift temperature and ionic-strength dependence were used, aided by molecular mechanics calculations. By modification of a pulse sequence designed for measuring long-range 1H-13C coupling constants, it was possible to obtain an accurate value for the 3JC2f-H1g despite the confounding presence of 3JHH of similar value. Free sucrose octasulfate appears to assume a conformation significantly different from any of the eight conformations observed bound to acidic fibroblast growth factor, as determined in a previous X-ray crystallographic study [X. Zhu, B.T. Hsu, and D.C. Rees, Structure, 1 (1993) 27-34]. Strong electrostatic interactions between guest and host may be the dominant factor in deformation of sucrose octasulfate. The implications of this study for protein-carbohydrate interactions and the effects of the presence of sulfate groups on the flexibility of sucrose are also discussed.
Shen
J
J
Department of Chemistry, University of Wisconsin, Madison 53706, USA.
Lerner
L E
LE
D000818:Animals; D000897:Anti-Ulcer Agents / Q000737:chemistry* / Q000378:metabolism; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D018360:Crystallography, X-Ray; D016220:Fibroblast Growth Factor 1 / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011485:Protein Binding; D013395:Sucrose / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism
D000897:Anti-Ulcer Agents; D016220:Fibroblast Growth Factor 1; D013395:Sucrose; C053081:sucrose octasulfate