Chemoenzymatic Synthesis of Heparin Oligosaccharides with both Anti-factor Xa and Anti-factor IIa Activities
Chemoenzymatic Synthesis of Heparin Oligosaccharides with both Anti-factor Xa and Anti-factor IIa Activities
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DOI：
10.1074/jbc.m112.358523
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发表时间：
2012-08-17
影响因子：
4.8
通讯作者：
Liu, Jian
中科院分区：
文献类型：
--
作者：
Xu, Yongmei;Pempe, Elizabeth H.;Liu, Jian
硫酸肝素（HS）和肝素是高度硫酸化的多糖。肝素是一种常用的抗凝药物，可抑制Xa和IIa因子（也称为凝血酶）的活性，以防止血栓形成。在这里，我们报道了一系列大小确定的低聚糖的合成，以探索具有抗iia活性的低聚糖的最小尺寸要求。通过糖基转移酶、HS硫基转移酶和c -5- epimase的化学酶法合成。我们证明了合成具有多达21个糖残基的高纯度n -亚砜寡糖的能力。抗xa和抗iia活性测定结果表明，长度大于19个糖基的寡糖才能显示抗iia活性。低聚糖还表现出与血小板因子4的低结合，提高了制备合成肝素的可能性，降低了肝素诱导的血小板减少症的影响。本研究的结果证明了合成大HS低聚糖的能力，并为探索需要使用大HS片段的HS结构和功能关系提供了独特的工具。
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.