title: Ascidian (Chordata-Tunicata) glycosaminoglycans: extraction, purification, biochemical, and spectroscopic analysis.
abstract: Sulfated polysaccharides with unique structures of the chondroitin/dermatan and heparin/heparan families of sulfated glycosaminoglycans have been described in several species of ascidians (Chordata-Tunicata). These unique sulfated glycans have been isolated from-ascidians and characterized by biochemical and spectroscopic methods. The ascidian glycans can be extracted by different tissues or cells by proteolytic digestion followed by cetylpyridinium chloride/ethanol precipitation. The total glycans are then fractionated by ion-exchange chromatography on DEAE-cellulose and/or Mono Q (HR 5/5) columns. Alternatively, precipitation with different ethanol concentrations can be employed. An initial analysis of the purified ascidian glycans is carried out by agarose gel electrophoresis on diaminopropane/acetate buffer, before or after digestion with specific glycosaminoglycan lyases or deaminative cleavage with nitrous acid. The disaccharides formed by exhaustive degradation of the glycans is purified by gel-filtration chromatography on a Superdex-peptide column and analyzed by HPLC on a strong ion exchange Sax-Spherisorb column. 1H or 13C nuclear magnetic resonance spectroscopy in one or two dimensions is used to confirm the structure of the intact glycans.
authors.affiliation: Laboratório de Bioquímica e Biologia Celular de Glicoconjugados, Programa de Glicobiologia, Instituto de Bioquímica Médica Leopoldo de Meis, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rua Professor Rodolpho Paulo Rocco, 255, 4° andar, sala 4A-08, Cidade Universitária, Ilha do Fundão, CEP 21941-913, Rio de Janeiro, Brazil, mpavao@hucff.ufrj.br.
authors.forename: Mauro S G
authors.initials: MS
authors.lastname: Pavão
mesh_terms: D000818:Animals; D011232:Chemical Precipitation; D004187:Disaccharides / Q000032:analysis; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D006025:Glycosaminoglycans / Q000032:analysis* / Q000302:isolation & purification*; D019763:Heparin Lyase / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D009608:Nitrous Acid / Q000737:chemistry; D009928:Organ Specificity; D014561:Urochordata / Q000737:chemistry*
chemical_list: D004187:Disaccharides; D006025:Glycosaminoglycans; D019763:Heparin Lyase; D009608:Nitrous Acid