| Autor: |
Zong C, Venot A, Li X, Lu W, Xiao W, Wilkes JL, Salanga CL; Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego , 9500 Gilman Drive MC0684, La Jolla, California 92093, United States., Handel TM; Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California-San Diego , 9500 Gilman Drive MC0684, La Jolla, California 92093, United States., Wang L, Wolfert MA; Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, and Bijvoet Center for Biomolecular Research, Utrecht University , Universiteitsweg 99, 3584 CG Utrecht, The Netherlands., Boons GJ; Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, and Bijvoet Center for Biomolecular Research, Utrecht University , Universiteitsweg 99, 3584 CG Utrecht, The Netherlands. |
| Abstrakt: |
Heparan sulfates (HS) are linear sulfated polysaccharides that modulate a wide range of physiological and disease-processes. Variations in HS epimerization and sulfation provide enormous structural diversity, which is believed to underpin protein binding and regulatory properties. The ligand requirements of HS-binding proteins have, however, been defined in only a few cases. We describe here a synthetic methodology that can rapidly provide a library of well-defined HS oligosaccharides. It is based on the use of modular disaccharides to assemble several selectively protected tetrasaccharides that were subjected to selective chemical modifications such as regioselective O- and N-sulfation and selective de-sulfation. A number of the resulting compounds were subjected to enzymatic modifications by 3-O-sulfotransferases-1 (3-OST1) to provide 3-O-sulfated derivatives. The various approaches for diversification allowed one tetrasaccharide to be converted into 12 differently sulfated derivatives. By employing tetrasaccharides with different backbone compositions, a library of 47 HS-oligosaccharides was prepared and the resulting compounds were used to construct a HS microarray. The ligand requirements of a number of HS-binding proteins including fibroblast growth factor 2 (FGF-2), and the chemokines CCL2, CCL5, CCL7, CCL13, CXCL8, and CXCL10 were examined using the array. Although all proteins recognized multiple compounds, they exhibited clear differences in structure-binding characteristics. The HS microarray data guided the selection of compounds that could interfere in biological processes such as cell proliferation. Although the library does not cover the entire chemical space of HS-tetrasaccharides, the binding data support a notion that changes in cell surface HS composition can modulate protein function. |
