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F S Wusteman

Publications and source records attributed to F S Wusteman.

34 records · Page 2Linked to original sources

The linkage region in the polypeptide of pig costal cartilage proteoglycan.

Proteoglycan from pig costal cartilage and fragments obtained by proteolytic digestion were characterized by equilibrium ultracentrifugation and amino acid analysis. The proteoglycan extractable in 4 M guanidinium chloride yielded, after proteolytic digestion with trypsin and chymotrypsin, a chondroitin sulfate peptide containing four chains of polysaccharide. The unextractable residue yielded chondroitin sulfate peptide containing only two chains. The amino acid composition indicated a fairly uniform spacing between all four chains with an average of eight amino acid residues between the serine residues involved in linkage. Following the alkaline sulfite elimination-addition reaction, free peptide was isolated and found to contain one unsubstituted serine residue for every two linked glycosidically. Glycine and glutamic acid were the only two amino acids sufficiently abundant to be part of an invariant sequence near to serine residues destined to be glycosylated. The linkage region of the polypeptide also contains some substituted serine residues which do not carry a full chondroitin sulfate chain.

Amino Acid Sequence↗

The degradation of intravenously injected chondroitin 4-sulphate in the rat.

The degradation of chondroitin 4-[(35)S]sulphate isolated from chick-embryo cartilage was studied in the rat by experiments on free-range animals, on wholly anaesthetized animals with ureter cannulae, by perfusion of isolated liver, by whole-body radioautography and by isolation of liver lysosomes. After injection into rats 68% of the radioactivity was recovered in the urine after 24h, approximately one-half of this being in the form of low-molecular-weight material, chiefly inorganic sulphate. Cannulation experiments demonstrated that the proportion of low-molecular-weight components excreted in the urine increased with time until, after 12h, virtually all was inorganic sulphate. Whole-body radioautography identified the liver as the major site of radioisotope accumulation after injection of labelled polysaccharide. Perfusion through isolated liver indicated that this organ has the ability to metabolize the polymer with the release of low-molecular-weight products, principally inorganic sulphate. Incubation of a lysosomal fraction prepared from rat liver after injection of chondroitin 4-[(35)S]sulphate gave rise to degradation products of low molecular weight, and experiments in vitro with rat liver lysosomes confirmed that these organelles are capable of the entire degradative process from chondroitin sulphate to free inorganic sulphate.

Animals↗

The glycosaminoglycans of human tracheobronchial cartilage.

1. The glycosaminoglycans of human tracheobronchial cartilages from subjects of various ages were liberated by proteolysis of the tissue and purified by ion-exchange chromatography. Purified glycosaminoglycans were fractionated on Dowex 1 resin and cetylpyridinium chloride was used to separate chondroitin sulphates and keratan sulphates occurring in the same fraction. 2. The total chondroitin sulphate content of the cartilages decreased linearly with increasing age. Age-dependent changes in the chemical heterogeneity of chondroitin sulphate were observed, a low-sulphated compound making up 25% of the total glycosaminoglycan at birth but rapidly diminishing in content during the first 6 months of life. Of the total chondroitin sulphate the 6-isomer became rather more prominent than the 4-isomer with increasing age. 3. The total keratan sulphate content of the cartilages increased from trace amounts only at birth to a plateau value by the beginning of the fifth decade. Of the total keratan sulphate approx. 70% was due to a high-molecular-weight compound with a sulphate/hexosamine ratio of 1.5-1.8: 1.0. The degree of sulphation varied between compounds isolated from different individuals. The remaining 30% of the keratan sulphate appeared to be intimately associated with chondroitin 6-sulphate and could only be separated from it after treatment with 0.45m-potassium hydroxide. The hybrid glycosaminoglycans were of lower molecular weight and had a lower sulphate/hexosamine ratio than the major keratan sulphate compound.

Adolescent↗

The detection and determination of L-tyrosine O-sulphate in rabbit and other mammalian urine.

A sensitive method using the Technicon Amino Acid Autoanalyzer was developed for the determination of l-tyrosine O-sulphate in mammalian urine. Normal rabbit urine was shown to contain a material that has properties identical with l-tyrosine O-sulphate. The material is also a normal constituent of rat, sheep, calf and mouse urine and is excreted by these animals in quantities ranging from 0.1 to 0.8mg./day/kg. body wt.

Animals↗

Alkali-labile luminol derivatives as labels for quantitative binding studies with polyionic macromolecules.

Acylated derivatives of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione) bearing a carboxyl or amino group can be linked by amide bonds to a macromolecule requiring labelling. Though themselves of low quantum yield these compounds are alkali-labile and can be detected at a similar level of sensitivity to the parent compound luminol. These cheap, readily accessible compounds are less hydrophobic than other currently employed chemiluminescent labels. They also lack a positively charged nitrogen atom which could complicate their covalent linkage to polyanionic compounds. They thus appear well suited for labelling heparin and other macromolecules which interact with the luminal surface of blood vessels.

Alkalies↗