MOLECULAR CHARACTERISTICS OF NATIVE HEPARIN AND REGIOSELECTIVELY DESULFATED HEPARIN: THE EFFECT OF SULFATE SUBSTITUENTS ON THEIR CONFORMATION

摘要

Native heparin and regioselectively desulfated heparin in aqueous solution were characterized in the presence of salt by means of static/dynamic light scattering and small-angle X-ray Scattering. The role of each sulfate group on conformation was discussed. A molecular model composed of a series of jointed cylindrical segments was proposed in order to account the scattering behavior of native and desulfated heparins in solution. Here a local conformation represented by a cylindrical segment is similar in native and desulfated heparins regardless the number and position of sulfate groups, but an overall conformation varies depending on the length of cylindrical segment. The length of a cylindrical segment seems to correlate with the sulfate pattern including the number and position of sulfate groups. The resulted data are further analyzed by adapting the molecular model and the effect of sulfate groups on the stability of heparin conformation was discussed by the model energy calculation.