Keratan sulfate

About: Keratan sulfate is a research topic. Over the lifetime, 1253 publications have been published within this topic receiving 57984 citations. The topic is also known as: keratan sulfate & KS.

Keratan sulfate proteoglycan isolated from the estrogen-induced medullary bone in Japanese quail.

Abstract: 1. 1. Two proteoglycans isolated from the femurs of quail actively producing medullary bone were separated using DEAE Bio-Gel A. 2. 2. The first to elute in the gradient was a keratan sulfate proteoglycan with an average buoyant density of 1.53 g/ml and a K av = 0.57 on Sepharose CL-4B. 3. 3. The second proteoglycan to elute contained chondroitin 4-sulfate. 4. 4. Apparently only the keratan sulfate proteoglycan is associated with the new medullary bone matrix.

Morquio's syndrome: a deficiency of chondroitin sulfate n-acetylhexosamine sulfate sulfatase

Abstract: Morquio's syndrome, an autosomal recessive disease exhibiting severe skeletal deformities and platyspondyly, is characterized by excretion of keratan sulfate and chondroitin sulfate. Extracts of cultured skin fibroblasts were found to contain normal levels of arylsulfatases A, B and C, β-N-acetylhexosaminidase, (β-glucuronidase and β-galactosidase. Incubation of extracts of Morquio fibroblasts with [35S]chondroitin sulfate (prepared from embryonic chick epiphyses) resulted in release of 2% of the 35SO4 in contrast to the release of 10-15% by extracts of normal, Hurler, Hunter or Sanfilippo A fibroblasts. Similar results were obtained when a heptasaccharide, GalNAc 35SO4-(GlcUA-GalNAc 35SO4)3, prepared from chondroitin sulfate, was incubated with lysosomal preparations from cultured fibroblasts. These findings indicate that Morquio's syndrome is due to a deficiency of a specific N-acetylhexosamine sulfate sulfatase. On the basis of the structures of the compounds excreted in Morquio's disease, it is likely that the deficient enzyme hydrolyzes 6-0-sulfate linkages in glycosaminoglycans. Supported by USPHS Grant Nos. AM-05996, HD-04583, AM-05589-06 and 2-Mol RR-00305-08.

Two linkage-region fragments isolated from skeletal keratan sulphate contain a sulphated N-acetylglucosamine residue.

Abstract: Peptido-keratan sulphate fragments were isolated from the nucleus pulposus of bovine intervertebral discs (6-year-old animals) after chondroitin ABC lyase digestion followed by digestion of A1D1 proteoglycans by diphenylcarbamoyl chloride-treated trypsin and gel-permeation chromatography on Sepharose CL-6B. Treatment of these peptido-keratan sulphate fragments with alkaline NaB3H4 yielded keratan sulphate chains with [3H]galactosaminitol end-labels, and these chains were further purified by gel-permeation chromatography on Sephadex G-50 and ion-exchange chromatography on a Pharmacia Mono-Q column in order to exclude any contamination with O-linked oligosaccharides. The chains were then treated with keratanase, and the digest was chromatographed on a Bio-Gel P-4 column followed by anion-exchange chromatography on a Nucleosil 5 SB column. Two oligosaccharides, each representing 18% of the recovered radiolabel, were examined by 500 MHz 1H-n.m.r. spectroscopy, and shown to have the following structures: [formula: see text] The structure of oligosaccharide (I) confirms the N-acetylneuraminylgalactose substitution at position 3 of N-acetylgalactosamine in the keratan sulphate-protein linkage region found by Hopwood & Robinson [(1974) Biochem. J. 141, 57-69] but additionally shows the presence of a 6-sulphated N-acetylglucosamine. Electron micro-probe analysis specifically confirmed the presence of sulphur in this sample. This sulphate ester group differentiates the keratan sulphate linkage region from similar structures derived from O-linked oligosaccharides [Lohmander, De Luca, Nilsson, Hascall, Caputo, Kimura & Heinegard (1980) J. Biol. Chem. 255, 6084-6091].