Heparinase

Enoxaparin sodium Dalteparin sodium Tinzaparin Nadroparin sodium Ardepatrin Benzylation followed by alkaline depolymerization Nitrous acid depolymerization Enz3miatic depolymerization with heparinase Nitrous acid depolymerization Peroxidative depolymerization... 

Conclusive evidence for the a-L configuration of the idosyluronic-to-hexosamine bond was provided by 1H-n.m.r. studies on disaccharide 7, obtained as the major product ( 75% yield) of the cleavage of heparin by heparinase.106 This configuration is consistent also with the 1H- and 13C-n.m.r. spectra of disaccharide 6 (the major product from nitrous acid cleavage of heparin103-106) and of unmodified heparin.82-84... 

In contrast to L-iduronic acid residues, most of which are sulfated at C-2, D-glucuronic acid residues in heparin and heparan sulfate are largely or exclusively nonsulfated. This was especially proved by their susceptibility to periodate oxidation,123 and through characterization of D-glucuronic acid-containing di- and tetra-saccharides from deamina-tive104 109 110 138 or heparinase - heparanase cleavage137,145 of heparin. 

Major Fragments from Exhaustive Depolymerization of Heparin with Nitrous Acid (A) and Heparinase (B)... 

Extracts of Flavobacterium heparinum that had been induced to grow on heparin-like polysaccharides contain a number of enzymes that may ultimately degrade heparin and heparan sulfate to monosaccharides.137,145 240 The enzymes that cause the primary cleavage of heparinlike chains are heparinase (EC 4.2.2.7) and heparanase (EC 4.2.2.8, formerly called heparitinase241,242). 

Heparinase and heparanase are lyases, that is, they cleave glycosidic linkages through elimination of water molecules. This cleavage, which occurs in a random, endolytic mode,243 between an aminohexosyl and a... 

As illustrated in Scheme 5, heparinase preferentially cleaves bonds... 

Scheme 5.—Typical Cleavage of Heparin (Arbitrary Sequence) with Heparinase (HEPase) and Heparanase (HSase). [Fragments longer than a tetrasaccharide may be obtained by separate use of each enzyme. The combined use of the two enzymes produces only disaccharides.]...

Although the size distribution of fragments from heparinase (and hep-aranase) digests reflects the relative content of regular sequences 5 in different heparin preparations and fractions, these sequences may be quantitated only when the enzyme efficiency is high, and products are... 

Figure 3.17. Effect of heparinase on the CHEQ of probe 13 with five equivalents of heparin. O. No heparinase A, 10 units heparinase O, 25 units heparinase -t-, 50 units heparinase. (Reproduced from Ref. 25. Copyright 1990 American Chemical Society.)...

Exhaustive digestion of porcine intestinal heparin with a mixture of bacterial heparinase and heparitinase I led to the isolation of two glycoserines (Table IV) in the molar ratio of 96 4.103a The major one is A4 5GlcA03Gal 33Gal04Xyip... 

Using heparinase and heparitinase from Flavobacterium heparinum, Buonassisi has provided evidence for the presence of heparan sulfate-containing proteoglycans in the plasma membranes of endothelial cells from rabbit aorta (73.74). 

C. Example 6 An Economic Analysis for Heparinase I Production from E. coli... 

The next two examples pursue this line of thought further wherein we analyze a computer-aided process of human insulin production.15 This is then followed by an analysis of process simulation of heparinase I production from E. coli.5... 

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