title: Examination of the substrate specificity of heparin and heparan sulfate lyases.
abstract: We have examined the activities of different preparations of heparin and heparan sulfate lyases from Flavobacterium heparinum. The enzymes were incubated with oligosaccharides of known size and sequence and with complex polysaccharide substrates, and the resulting degradation products were analyzed by strong-anion-exchange high-performance liquid chromatography and by oligosaccharide mapping using gradient polyacrylamide gel electrophoresis. Heparinase (EC 4.2.2.7) purified in our laboratory and a so-called Heparinase I (Hep I) from a commercial source yielded similar oligosaccharide maps with heparin substrates and displayed specificity for di- or trisulfated disaccharides of the structure----4)-alpha-D-GlcNp2S(6R)(1----4)-alpha-L-IdoAp2S( 1----(where R = O-sulfo or OH). Oligosaccharide mapping with two different commercial preparations of heparan sulfate lyase [heparitinase (EC 4.2.2.8)] indicated close similarities in their depolymerization of heparan sulfate. Furthermore, these enzymes only degraded defined oligosaccharides at hexosaminidic linkages with glucuronic acid:----4)-alpha-D-GlcNpR(1----4)-beta-D-GlcAp(1----(where R = N-acetamido or N-sulfo). The enzymes showed activity against solitary glucuronate-containing disaccharides in otherwise highly sulfated domains including the saccharide sequence that contains the antithrombin binding region in heparin. A different commercial enzyme, Heparinase II (Hep II), displayed a broad spectrum of activity against polysaccharide and oligosaccharide substrates, but mapping data indicated that it was a separate enzyme rather than a mixture of heparinase and heparitinase/Hep III. When used in conjunction with the described separation procedures, these enzymes are powerful reagents for the structural/sequence analysis of heparin and heparan sulfate.
authors.affiliation: Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City 52242.
authors.forename: R J
authors.initials: RJ
authors.lastname: Linhardt
authors.forename: J E
authors.initials: JE
authors.lastname: Turnbull
authors.forename: H M
authors.initials: HM
authors.lastname: Wang
authors.forename: D
authors.initials: D
authors.lastname: Loganathan
authors.forename: J T
authors.initials: JT
authors.lastname: Gallagher
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005417:Flavobacterium / Q000201:enzymology*; D006025:Glycosaminoglycans; D006493:Heparin / Q000378:metabolism*; D015394:Molecular Structure; D009844:Oligosaccharides; D011133:Polysaccharide-Lyases / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D006025:Glycosaminoglycans; D009844:Oligosaccharides; D006493:Heparin; D011133:Polysaccharide-Lyases; C021349:heparitinsulfate lyase