title: Purification and characterization of heparin from the Italian clam Callista chione.
abstract: An unusual heparin (approximately 1.9 mg/g of dry tissue) was isolated from the marine italian bivalve mollusk Callista chione. Agarose gel electrophoresis showed a high content of the fast-moving heparin component (85 +/- 7.6%) and 15 +/- 1.3% of the slow-moving species. An average molecular mass of 10 950 was calculated by PAGE analysis. The anticoagulant properties were measured as APTT (97 +/- 12.1 IU/mg) and anti-Xa activity (52 +/- 7.4 IU/mg). Structural analysis of clam heparin, performed by depolymerizing heparin samples with heparinase (EC 4.2.2.7) and then separating the resulting unsaturated oligosaccharides by SAX-HPLC, revealed the presence of low amounts of the trisulfated disaccharide [DeltaUA2S(1-->4)-alpha-d-GlcN2S6S] and a significant increase of the disaccharides bearing nonsulfated iduronic and glucuronic acids, [-->4)-alpha-l-IdoA(1-->4)-alpha-d-GlcNAc6S(1-->] and [-->4)-alpha-l-IdoA(1-->4)-alpha-d-GlcN2S6S(1-->], and [-->4)-beta-d-GlcA(1-->4)-alpha-d-GlcN2S6S(1-->]. As a consequence, Callista chione heparin is a low-sulfated polysaccharide showing a specific decrease of the sulfatation in position 2 of the uronic acid units.
authors.affiliation: Department of Biologia Animale, University of Modena and Reggio Emilia, Via Campi 213/D, 41100 Modena, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Luppi
authors.forename: Marina
authors.initials: M
authors.lastname: Cesaretti
authors.forename: Nicola
authors.initials: N
authors.lastname: Volpi
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D006493:Heparin / Q000737:chemistry* / Q000302:isolation & purification*; D007558:Italy
chemical_list: D006493:Heparin