Heparin lyases

Lohse DL, Linhardt RJ (1992) Purification and characterization of heparin lyases from Flavobacterium heparinum. J Biol Chem 267 24347-55. 

Early work on heparin and heparan sulfate was mainly concerned with isolation and identification of di- and tetra-saccharides. The main product of heparin lyase action on bovine-liver heparin was276 the unsaturated,... 

The constitutions of bovine-lung and -kidney, as well as of porcine-kidney, heparan sulfates have been compared after quantitative digestion with a mixture of heparin lyase and heparan sulfate lyase, followed by separation of the unsaturated disaccharides by liquid chromatography under elevated... 

A comparison of size distribution of oligosaccharides released by heparin lyase digestion of pig-mucosal heparin with those calculated theoretically,2853 was consistent with a random distribution of cleavage sites within... 

A glycosaminoglycan isolated from lobsters was examined with heparin lyase and heparan sulfate lyase.275 It was degraded much less extensively than beef-liver heparin by the former, and not degraded by the latter, indicating a structure intermediate between those of heparin and heparan sulfate. Heparan sulfates from three species of mollusks219 were found to be resistant to heparin lyase action. With heparan sulfate lyase, similar oligosaccharides in different proportions were obtained. Comparison with the products from bovine-pancreatic heparan sulfate showed the same oligosaccharides. 

Fig. 3. Substrate specificity of heparin lyases. The arrows indicate the glucosaminidic linkages cleaved by the enzymes. Both configurations of the carboxylate group are shown when both IdoA and GlcA are compatible with lyase action. An unsubstituted hydroxyl group at C-3 of the GlcN residue toward the reducing end is a prerequisite for susceptibility to lyases II and III. Other groups essential for cleavage with the indicated enzyme are shown in bold type. (Adapted from Ref. 98.)...

Combined incubation with the three heparin lyases eventually converts heparin and HS to disaccharides, the only sequence invariably resistant to cleavage being the linkage region. "" The HPLC profiles of the disaccharide pools thus obtained are conveniently used for compositional characterization of heparins and HS of different origin notably, however, information regarding GlcA/IdoA ratio is lost. 

Disaccharides Generated by Exhaustive Digestion of Heparin/HS with Heparin Lyase (A, Refs. 122—125) and with Nitrous Acid (B, Refs. 150, 155-157). (a) from IdoA-containing Sequences (b) from GlcA-containing Sequences. 

Lyases are effective enzymes for the degradation of polysaccharides. Examples are pectin lyase, pectate lyase, xanthan lyase, alginate lyase, hyaluronate lyase, and heparin lyase. BioPreparation , which was developed by NOVOZYIVIES A/S for the removal of polymeric materials from the cotton surface, contains the pectate lyase (5). 

Heparin Lyases and Heparan Sulphate Lyases The isolation and partial characterization of a heparin lyase and two heparan sulphate lyases from Flavobacterium heparinum have been reported. ... 

Heparin was prepared in 5 mM sodium phosphate buffer (pH 7.0) containing 150 mM sodium chloride at 10 mg/mL. To 80 pi of heparin, 20 pi of heparin lyase (0.03 lU in the same buffer) was added. The reaction mixture was incubated overnight at 30 C. After the reaction was complete, protein was removed from the reaction mixture by adjusting its pH to 3.0 and passing this solution through a 1 mL column of sulfopropyl-Sephadex adjusted with 30 mM hydrochloric acid to the same pH. The material fail-... 

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