OCCURRENCE OF SULFATED PYRANOSIC ARABINANS IN CELL WALLS FROM GREEN ALGAE

PAULA X. ARATA; FERNÁNDEZ, PAULA VIRGINIA; MARINA CIANCIA; IRENE QUINTANA

Smolenice

Simposio; 14th Bratislava Symposium on Saccharides, "Glycochemistry for biology and medicine"; 2017

Institute of Chemistry, Center for Glycomics, Slovak Academy of Sciences

OCCURRENCE OF SULFATED PYRANOSIC ARABINANS IN CELL WALLS FROM GREEN ALGAE Marina Cianciaa,b, Paula Ximena Arataa, Paula Virginia Fernándeza,b, Irene Quintanac aUniversidad de Buenos Aires, Facultad de Agronomía, Departamento de Biología Aplicada y Alimentos, Cátedra de Química de Biomoléculas, Av. San Martín 4453, C1417DSE Buenos Aires, Argentina. bCONICET-Universidad de Buenos Aires, CIHIDECAR, Ciudad Universitaria ? Pabellón 2, C1428EHA Buenos Aires, Argentina. cUniversidad de Buenos Aires, Facultad de Ciencia Exacta y Naturales, Departamento de Química Biológica, Laboratorio de Hemostasia y Trombosis, Ciudad Universitaria ? Pabellón 2, C1428EHA Buenos Aires, Argentina.ciancia@agro.uba.arSulfated polysaccharides from green seaweeds can be divided into two main groups, based on the occurrence of uronic acids. In the last years, we studied structures of polysaccharides from the orders Bryopsidales and Cladophorales, comprising galactose and arabinose, as major sugars. We isolated important amounts of arabinans from several species of Codium (Bryopsidales), which are highly sulfated pyranosic 3-linked -L-arabinans, other species do not produce these kind of polysaccharides. Recently, we began to study sulfated polysaccharides from the Cladophorales, and also found sulfated pyranosic arabinans, but in this case, they have a backbone constituted by 4-linked -L-arabinose units. It has been proposed that the presence of sulfated polysaccharides in cell walls of seaweeds is a consequence of the physiological adaptation to the marine environment. However, we found sulfated polysaccharides in a fresh water alga of this order and determined that its structure has many common structural features with those of the marine species. This result is surprising, as it has always been believed that sulfated polysaccharides were not present in cell walls from fresh water organisms.We studied the anticoagulant activity of these arabinans, the mechanisms of action and kinetics of fibrin formation and fibriniolysis.Although the pyranose form of L-arabinose is thermodynamically more stable, in nature, it occurs mostly in the furanose form. Nevertheless, our work shows that sulfated pyranosic arabinans are widespread in green algae.