Isolation and characterization of the glycosaminoglycan component of rabbit thrombomodulin proteoglycan

Journal Article · Sat Sep 15 00:00:00 EDT 1990 · Journal of Biological Chemistry; (USA)

OSTI ID:6511778

Bourin, M C; Lundgren-Akerlund, E; Lindahl, U ^[1]

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1. Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

Previous studies on rabbit thrombomodulin (TM) revealed that certain anticoagulant activities expressed by TM depend on the presence of an acidic domain tentatively identified as a sulfated galactosaminoglycan. The glycan was released by alkaline beta-elimination, isolated by ion-exchange chromatography, and radiolabeled by partial N-deacetylation (hydrazinolysis) followed by re-N-(3H)acetylation. The labeled product behaved like standard chondroitin sulfate on ion-exchange chromatography, exhibited a Mr of 10-12 x 10(3) on gel chromatography, and was susceptible to degradation by chondroitinase and testicular hyaluronidase. The major labeled degradation products following digestion of the glycosaminoglycan with chondroitinase were identified, depending on the incubation conditions, either as 4/6-mono-O-sulfated, 4,5-unsaturated disaccharides (delta HexA-GalNAc)S and N-acetylgalactosamine 4,6-di-O-sulfate GalcNAc (diS), the latter component accounting for approximately 25% of the total label, or as a major fraction of labeled trisaccharide, with the predominant structure GalNAc(diS)-GlcA-GalNAc(diS). The terminal GalNAc(diS) unit (not substituted at C3) was shown to be more susceptible to N-deacetylation during hydrazinolysis than were the internal GalNAc units (substituted at C3), and thus was more extensively labeled, resulting in over-representation of this unit. It is concluded that rabbit TM is a chondroitin sulfate proteoglycan, which carries a single glycan side chain characterized by an unusual accumulation of sulfate groups at the nonreducing terminus. Metabolically 35S-labeled TM was isolated from cultured rabbit heart endothelial cells and characterized as a chondroitin sulfate proteoglycan which accounted for 1-2% of the total 35S-labeled cell-associated macromolecules.

• OSTI ID: 6511778
• Journal Information: Journal of Biological Chemistry; (USA), Journal Name: Journal of Biological Chemistry; (USA) Vol. 265:26; ISSN 0021-9258; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLATION
ACYLATION
ANIMAL TISSUES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CELL CULTURES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
ENDOTHELIUM
ENZYMES
EVEN-ODD NUCLEI
GLYCOPROTEINS
ION EXCHANGE CHROMATOGRAPHY
ISOTOPE APPLICATIONS
ISOTOPE DILUTION
ISOTOPES
LIGHT NUCLEI
LYASES
MAMMALS
NUCLEI
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PROTEINS
RABBITS
RADIOISOTOPES
SEPARATION PROCESSES
SULFATES
SULFUR 35
SULFUR COMPOUNDS
SULFUR ISOTOPES
TISSUES
TRACER TECHNIQUES
VERTEBRATES