Department of Chemistry, University of California, Riverside, California 92521, USA.
Annu Rev Anal Chem (Palo Alto Calif). 2011;4:439-65. doi: 10.1146/annurev-anchem-061010-113911.
Although heparin is an important and widely prescribed pharmaceutical anticoagulant, its high degree of sequence microheterogeneity and size polydispersity make molecular-level characterization challenging. Unlike nucleic acids and proteins that are biosynthesized through template-driven assembly processes, heparin and the related glycosaminoglycan heparan sulfate are actively remodeled during biosynthesis through a series of enzymatic reactions that lead to variable levels of O- and N-sulfonation and uronic acid epimers. As summarized in this review, heparin sequence information is determined through a bottom-up approach that relies on depolymerization reactions, size- and charge-based separations, and sensitive mass spectrometric and nuclear magnetic resonance experiments to determine the structural identity of component oligosaccharides. The structure-elucidation process, along with its challenges and opportunities for future analytical improvements, is reviewed and illustrated for a heparin-derived hexasaccharide.
尽管肝素是一种重要且广泛应用的医药抗凝剂，但由于其高度的序列微观不均一性和尺寸多分散性，对其进行分子水平的特征描述具有一定挑战性。与通过模板驱动的组装过程生物合成的核酸和蛋白质不同，肝素和相关的糖胺聚糖硫酸乙酰肝素在生物合成过程中通过一系列酶促反应进行主动重塑，导致不同程度的 O-和 N-磺酸化和糖醛酸差向异构体。正如本文综述中所总结的那样，肝素序列信息是通过一种自下而上的方法确定的，该方法依赖于解聚反应、基于大小和电荷的分离以及灵敏的质谱和核磁共振实验，以确定组成寡糖的结构同一性。本文对肝素衍生的六糖进行了结构解析过程的回顾，并讨论了其未来分析改进的挑战和机遇。
