STUDIES ON THE POLYSACCHARIDE-SULFATING SYSTEM IN SEA URCHIN EMBRYOS: II. NATURE OF SULFATED MATERIALS PRODUCED IN A CELL-FREE SYSTEM 1

Sulfated polysaccharides produced by the reaction which transfers sulfate from 3'-phosphoadenosine 5'-phosphosulfate to endogenous acceptors in sea urchin embryos were characterized by their precipitability with cetylpyridinium chloride, chromatographic behavior on DEAE-cellulose and Sephadex G-75 columns, and digestibility with chondroitinase ABC and AC. One component of the sulfated polysaccharides was identified as dermatan sulfate (DS). The others were chondroitinase ABC-resistant and separable into large (SPL) and small (SPS) molecular polysaccharides by Sephadex G-75 column chromatography. Sulfate incorporation into SPL was always higher than incorporation into DS or SPS and the activity for sulfate incorporation into DS was lost most rapidly during storage of the particulate fraction at 14°C. Sulfate incorporation into the three components was low at the morula stage and then increased during development to the mesenchyme blastula stage. From the mesenchyme blastula to the pluteus stage, incorporation into SPL increased and that into SPS remained constant. Incorporation into DS was maximal from the blastula to the late gastrula stage and became low at the pluteus stage.