Localization and characterization of acharan sulfate in the body of the giant African snail Achatina fulica

Acharan sulfate is a glycosaminoglycan (GAG), having the structure --> 4)-2 -acetamido-2-deoxy-alpha -D-glucopyranose(1 --> 4)-2-sulfo-alpha -L-idopyra nosyluronic acid (1 -->), isolated from the body of the giant African snail Achatina fulica. This GAG represents 3-5% of the dry weight of this snail' s soft body tissues. Frozen sections and polyester wax sections of the snai l's body were stained by Alcian blue-periodic acid-Schiff's reagent (PAS) t o localize acharan sulfate. Alcian blue staining indicated that GAG was mai nly secreted into the outer surface of the body from internal granules. A h ighly mucous material was collected and treated and the acharan sulfate was recovered by ethanol and cetyl pyridinium chloride precipitation. Crude ac haran sulfate was purified by DEAE-Sephacel ion-exchange chromatography. De polymerization of intact mucus and purified acharan sulfate fractions by he parin lyase II (heparitinase I) from Flavobacterium heparinum produced an u nsaturated disaccharide as a major product, establishing the repeating unit of acharan sulfate. These results demonstrate that mucus in the granule an d secreted to the outside of the body is composed entirely of acharan sulfa te. (C) 2001 Elsevier Science Inc. All rights reserved.