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Crude glycosaminoglycan (GAG) fraction was directly precipitated with cetylpyridinium chloride without prior dialysis of urine of orthopedic patients. The crude GAG fraction was then fractionated with trichloroacetic acid (TCA). The TCA-insoluble peptide-bound GAG fraction thus obtained was treated with alkali to eliminate the peptide moiety for enzymatic analysis. The GAG compositions of this fraction and the TCA-soluble fraction were determined by digestion with mucopolysaccharidases (chondroitinase AC, chondroitinase B, chondroitinase C, heparitinase and Streptomyces hyaluronidase). When the amount of the crude GAG fraction was small, no significant amount of the TCA-insoluble peptide-bound GAG fraction was obtained. The GAG composition of this case was also determined by the same procedures after direct alkali-treatment of the crude GAG fraction. The data indicated that the proportion of the TCA-insoluble peptide-bound GAG fraction was very small. The alkali-treated TCA-insoluble peptide-bound GAG fraction contained a larger proportion of heparan sulfate than the TCA-soluble GAG fraction. It was clearly demonstrated that the patients with Werner's syndrome and mucopolysaccharidosis I-S (Scheie) excreted large amounts of hyaluronic acid and dermatan sulfate respectively, into urines. It was indicated in most cases that major urinary GAG were chondroitin 4-sulfate, chondroitin 6-sulfate plus chondroitin and heparan sulfate, while minor ones were dermatan sulfate and hyaluronic acid. In addition, the data suggested a wide range of the degree of desulfation or urinary GAG, and the presence of significant amounts of keratan sulfate plus acidic glycopeptides in the urinary GAG fractions. The present data provided more precise information on urinary GAG from orthopedic patients than those reported previously.

The chemical structure of dermatan sulfate (DS) in the urine of a patient the Hunter syndrome was studied through the analysis of disaccharide units which were derived from the urinary DS by digestion with chondroitinase ABC and separated on a Dowex 1 column. The DS was basically composed of repeating disaccharide units of iduronyl N-acetylgalactosamine 4-sulfate. About 90% of the excess sulfate were linked to the iduronate residues as an additional sulfate group in the unit. N-Acetylgalactosamine 6-sulfate and N-acetylgalactosamine 4,6-disulfate residues were minor components. No non-sulfated disaccharide unit was detected in the digestion products. Only sulfoiduronate residue was found as the non-reducing terminal sugar of the DS molecule, consistent with the lack of iduronosulfate sulfatase in this disease.

To elucidate precise nature of urinary glycosaminoglycans (GAG) GAG in the acidic subfractions obtained in a previous paper (Endo et al. 1980) were quantitated by digestion with mucopolysaccharidases, nitrous acid treatment and by quantitative cellulose acetate membrane (Separax) electrophoresis. Hyaluronic acid, chondroitin sulfates and chondroitin, dermatan sulfate and dermatan, heparan sulfate, keratan sulfate, and acidic glycopeptide were found in wide distribution in these subfractions. The results suggested the presence of various degree of the depolymerization products of each GAG and of wide range of the desulfation products of each sulfated GAG. Distribution map of each GAG in the subfractions showed more detailed polydispersity of GAG in normal human urine than that reported previously.

Glycosaminoglycan isolated from the urine of a patient with the Hunter syndrome was composed of heparan sulfate (59.9%), dermatan sulfate (30.6%) and chondroitin sulfate (9.5%), and was heterogeneous in molecular weight (1,500-10,000) and in sulfate content (0.35-2.05 moles/mole of hexosamine). About 60% of dermatan sulfate and 10% of heparan sulfate had molecular weight of 7,000 to 10,000, while about 10% of the former and 60% of the latter had those of 1,500 to 3,500. Sulfate contents of dermatan sulfate and heparan sulfate were inversely related to their molecular weights. Higher total- and N-sulfate contents were measured in smaller molecular-weight heparan sulfate, and higher acetyl content was in larger molecular-weight heparan sulfate. On the basis of the chemical properties of dermatan sulfate and heparan sulfate isolated in this experiment, their catabolic processes in the Hunter syndrome were discussed.