title: Chemoenzymatic synthesis of heparin oligosaccharides with both anti-factor Xa and anti-factor IIa activities.
abstract: Heparan sulfate (HS) and heparin are highly sulfated polysaccharides. Heparin is a commonly used anticoagulant drug that inhibits the activities of factors Xa and IIa (also known as thrombin) to prevent blood clot formation. Here, we report the synthesis of a series of size-defined oligosaccharides to probe the minimum size requirement for an oligosaccharide with anti-IIa activity. The synthesis was completed by a chemoenzymatic approach involving glycosyltransferases, HS sulfotransferases, and C(5)-epimerase. We demonstrate the ability to synthesize highly purified N-sulfo-oligosaccharides having up to 21 saccharide residues. The results from anti-Xa and anti-IIa activity measurements revealed that an oligosaccharide longer than 19 saccharide residues is necessary to display anti-IIa activity. The oligosaccharides also exhibit low binding toward platelet factor 4, raising the possibility of preparing a synthetic heparin with a reduced effect of heparin-induced thrombocytopenia. The results from this study demonstrate the ability to synthesize large HS oligosaccharides and provide a unique tool to probe the structure and function relationships of HS that require the use of large HS fragments.
authors: Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
authors: Yongmei
authors: Y
authors: Xu
authors: Elizabeth H
authors: EH
authors: Pempe
authors: Jian
authors: J
authors: Liu
mesh_terms: D000925:Anticoagulants / Q000138:chemical synthesis* / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry*; D015951:Factor Xa / Q000737:chemistry; D065427:Factor Xa Inhibitors; D016695:Glycosyltransferases / Q000737:chemistry*; D006493:Heparin / Q000138:chemical synthesis* / Q000494:pharmacology; D006801:Humans; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000494:pharmacology; D016979:Pasteurella multocida / Q000201:enzymology*; D011516:Prothrombin / Q000037:antagonists & inhibitors* / Q000737:chemistry
chemical_list: D000925:Anticoagulants; D001426:Bacterial Proteins; D065427:Factor Xa Inhibitors; D009844:Oligosaccharides; D011516:Prothrombin; C025337:Factor IIa; D006493:Heparin; D016695:Glycosyltransferases; C450833:heparosan synthase; D015951:Factor Xa