Structural properties of the heparan sulfate proteoglycans of brain

• Published in: Journal of neurochemistry Vol. 52; no. 3; p. 807
• Main Authors: Ripellino, J A, Margolis, R U
• Format: Journal Article
• Language: English
• Published: England 01.03.1989
• Subjects: Animals; Brain Chemistry; Centrifugation, Density Gradient; Chemical Phenomena; Chemistry; Chondroitin Sulfate Proteoglycans - isolation & purification; Chondroitin Sulfate Proteoglycans - metabolism; Chondroitin Sulfates - analysis; Chromatography, Affinity; Chromatography, Gel; Chromatography, Ion Exchange; Glycosaminoglycans - isolation & purification; Heparan Sulfate Proteoglycans; Heparin Lyase; Heparitin Sulfate - analysis; Heparitin Sulfate - isolation & purification; Heparitin Sulfate - metabolism; Molecular Structure; Molecular Weight; Polysaccharide-Lyases - metabolism; Protein Multimerization; Proteoglycans - isolation & purification; Rats; Sulfates - metabolism
• ISSN: 0022-3042
• DOI: 10.1111/j.1471-4159.1989.tb02525.x

The heparan sulfate proteoglycans present in a deoxycholate extract of rat brain were purified by ion exchange chromatography, affinity chromatography on lipoprotein lipase agarose, and gel filtration. Heparitinase treatment of the heparan sulfate proteoglycan fraction (containing 86% heparan sulfate and 10% chondroitin sulfate) that was eluted from the lipoprotein lipase affinity column with 1 M NaCl led to the appearance of a major protein core with a molecular size of 55,000 daltons, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Comparison of the effects of heparinase and heparitinase treatment revealed that the heparan sulfate proteoglycans of brain contain a significant proportion of relatively short N-sulfoglucosaminyl 6-O-sulfate [or N-sulfoglucosaminyl](alpha 1-4)iduronosyl 2-O-sulfate(alpha 1-4) repeating units and that the portions of the heparan sulfate chains in the vicinity of the carbohydrate-protein linkage region are characterized by the presence of D-glucuronic acid rather than L-iduronic acid. After chondroitinase treatment of a proteoglycan fraction that contained 62% chondroitin sulfate and 21% heparan sulfate (eluted from lipoprotein lipase with 0.4 M NaCl), the charge and density of a portion of the heparan sulfate-containing proteoglycans decreased significantly. These results indicate that a population of "hybrid" brain proteoglycans exists that contain both chondroitin sulfate and heparan sulfate chains covalently linked to a common protein core.