Zhongping Xiao

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Heparin and HS (heparan sulfate) exert their wide range of biological activities by interacting with extracellular protein ligands. Among these important protein ligands are various angiogenic growth factors and cytokines. HS binding to VEGF (vascular endothelial growth factor) regulates multiple aspects of vascular development and function through its(More)
Seven pharmaceutical heparins were investigated by oligosaccharide mapping by digestion with heparin lyase 1, 2, or 3, followed by high performance liquid chromatography analysis. The structure of one of the prepared mapping standards, ΔUA-Gal-Gal-Xyl-O-CH(2)CONHCH(2)COOH (where ΔUA is 4-deoxy-α-l-threo-hex-4-eno-pyranosyluronic acid, Gal is(More)
Seven commercial heparin active pharmaceutical ingredients and one commercial low molecular weight from different manufacturers were characterized with a view profiling their physicochemical properties. All heparins had similar molecular weight properties as determined by polyacrylamide gel electrophoresis (M(N), 10-11 kDa; M(W), 13-14 kDa; polydispersity(More)
Zhongping Xiao2,3, Wenjing Zhao4, Bo Yang3, Zhenqing Zhang3, Huashi Guan1,2, and Robert J Linhardt1,3,4,5 Key Laboratory of Marine Drugs, Chinese Ministry of Education, Institute of Marine Drug and Food, Ocean University of China, Qingdao 266003, China; Department of Chemistry and Chemical Biology, Department of Biology, and Department of Chemical and(More)
Porcine intestinal mucosa heparin was partially depolymerized by recombinant heparinase 1 (heparin lyase 1, originating from Flavobacterium heparinum and expressed in Escherichia coli) and then fractionated, leading to the isolation of 22 homogeneous oligosaccharides with sizes ranging from disaccharide to hexadecasaccharide. The purity of these(More)
Thin layer chromatography (TLC) is routinely used by synthetic organic chemists and natural products chemists working on a variety of types of molecules. Carbohydrate chemists and biochemists in the past largely relied on paper chromatography for rapid and inexpensive analysis. Carbohydrates are highly polar molecules and often require derivatization to be(More)
Heparin and heparan sulfate contain a rare 3-O-sulfoglucosamine residue critical for anticoagulation and virus recognition, respectively. The glycosidic linkage proximate to this 3-O-sulfoglucosamine is resistant to cleavage by all heparin lyases (Heps). HepII has a broad specificity. The crystal structure of the wild type HepII identified its active site(More)
A quantitative analysis of a recalled contaminated lot of heparin sodium injection U.S. Pharmacopeia (USP) was undertaken in response to the controversy regarding the exact nature of the contaminant involved in the heparin (HP) crisis. A mass balance analysis of the formulated drug product was performed. After freeze-drying, a 1-ml vial for injection(More)
Heparin glycosaminoglycans (GAGs) present the most difficult glycoform for analytical characterization due to high levels of sulfation and structural heterogeneity. Recent contamination of the clinical heparin supply and subsequent fatalities has highlighted the need for sensitive methodologies of analysis. In the last decade, tandem mass spectrometry has(More)
  • Young-Hyun Han, Marie-Line Garron, +10 authors Miroslaw Cygler
  • The Journal of biological chemistry
  • 2009
Heparin lyase I (heparinase I) specifically depolymerizes heparin, cleaving the glycosidic linkage next to iduronic acid. Here, we show the crystal structures of heparinase I from Bacteroides thetaiotaomicron at various stages of the reaction with heparin oligosaccharides before and just after cleavage and product disaccharide. The heparinase I structure is(More)