Cellulose column chromatography for the fractionation and isolation of acid mucopolysaccharides

Connective tissue metabolism in children with chronic renal failure

To assess the characteristics of connective tissue metabolism in chronic renal failure (CRF), urinary excretion of glycosaminoglycan (GAG) fractions and hydroxyproline (HYP) was determined in ten patients with CRF and in ten age-matched healthy children. CRF was found to be associated with elevated free HYP (19.9 +/- 6.1 vs 9.8 +/- 3.6 mumol/day, P less than 0.05) and depressed peptide HYP excretion (33.1 +/- 13.5 vs 225.2 +/- 17.7 mumol/day, P less than 0.01), a low rate of total GAG excretion (7.0 +/- 2.4 vs 16.1 +/- 1.9 mumol uronic acid/day, P less than 0.05) with low chondroitin 4 -sulphate + chondroitin 6 -sulphate (Ch-Ss) (14.0 +/- 9.9 vs 65.0 +/- 22.1%) and a high proportion of non-sulphated or under-sulphated fractions, i.e. hyaluronic acid + chondroitin + heparan sulphate (HA + Ch + HS) (75.3 +/- 11.4 vs 31.5 +/- 5.7%). Urinary 3-methyl-histidine (3-met-HIS) excretion and plasma essential free amino acids did not differ in the two groups. In response to haemodialysis no consistent change occurred in urinary excretion of 3-met-HIS, peptide-bound HYP, total GAG or percentage distribution of individual GAG fractions. After haemodialysis all plasma amino acids decreased significantly, and there was a significant increase in urinary excretion of free HYP (P less than 0.05). We conclude that the alterations in urinary excretion of total and individual GAGs observed in CRF may reflect disturbed connective tissue metabolism which does not appear to be accounted for by protein malnutrition or enhanced protein breakdown and remains uninfluenced by haemodialysis therapy.

Isolation and characterization of peptidoglycans in urine from patients with mucopolysaccharidoses

Urinary dermatan sulfate (DS) and heparan sulfate (HS) were purified from mucopolysaccharidosis patients. DS shows average mol. wt 8600-12,000 (approx. one half of tissue DS), iduronic acid content 99.1-99.6% (81.8% in tissue DS), core peptide mostly di- or tri-peptide (--Ser--Gly--or--Ser--Gly--Glu--). Molecular weight of HS ranged from 2500 to 20,000, averaging about 5000. Highly sulfated HS was found in the low molecular weight fraction, and no bound core peptide. By contrast, HS in the high molecular weight fraction bound one sulfate per repeating unit, which include core peptide.

[Preparative electrophoresis of peptidic glycosaminoglycans. Application to the fractionation of peptidic glycosaminoglycans of arterial wall (author's transl)]

A new procedure for the fractionation of glycosaminoglycans by electrophoresis on Pevikon has been described. Mixtures of glycosaminoglycans were fractionated by preparative electrophoresis on Pevikon in pyridine formate or glycine-HCl buffers. By this procedure, 200 mg of a mixture of hyaluronic acid, heparan sulphate, dermatan sulphate and chondroitin sulphate isolated from arterial wall could be successfully separated without loss of material. The purified fractions were analysed by enzymatic and chemical procedures. The molar ratios of uronic acid to hexosamine and of sulphate to hexosamine and the amino acid content of each glycosaminoglycan have been determined. The peptidic content (less than 1%) is represented by five amino acids, viz. serine, glycine, alanine, aspartic acid, and glutamic acid.

Bovine adrenal medullary chromogranin A: studies on the structure and further evidence for identity with dopamine-beta-hydroxylase subunit

1. Chromogranin A was purified by the use of polyacrylamide gel electrophoresis. The amino acid composition of chromogranin A appeared to be nearly identical to that reported by other investigators and, moreover, was confirmed to be similar to that of dopamine beta-hydroxylase. 2. Dansyl-end group analysis revealed the presence of leucine as the only amino-terminal residue and quantitative estimations showed the presence of two leucine residues per molecule of 77 000 molecular weight. 3. Tryptic and CNBr patterns were obtained. Data are in good agreement with the concept of two nearly identical polypeptide chains per chromogranin A molecule of mol. wt 77 000. Patterns were compared with those obtained in parallel dopamine beta-hydroxylase and support the idea that chromogranin A and the dopamine beta-hydroxylase subunit are identical. Digestion with leucine amino peptidase gave further additional evidence for this suggestion. 4. Chromogranin A appeared to be free of carbohydrates. No cross-reaction was detected between chromogranin A and rabbit antibody against bovine adrenal dopamine beta-hydroxylase.