Biomaterial Database

Biosynthesis of chondroitin sulfate. Chain termination. 1978

J E Silbert

Incubation of chick embryo epiphyseal microsomal preparations with either UDP-[14C]GlcUA or UDP-[14C]-GalNAc plus exogenous chondroitin 6-sulfate resulted in the incorporation of either a single [14C]GlcUA or a [14C]GalNAc onto the nonreducing ends of the exogenous glycosaminoglycan. Degradation by chondroitinase ABC yielded the terminal products [14C]Di-OS, [14C]Di-6S, and [14C]GalNAc. Incubations of the microsomal preparations with either UDP-[14C]GlcUA or UDP-GalN[3H]Ac without exogenous chondroitin 6-sulfate resulted in the addition of a single sugar onto the nonreducing end of endogenous chondroitin sulfate. Degradation by chondroitinase ABC yielded the terminal products [14C]Di-OS, [14C]Di-6S, and GalN[3H]Ac in a molar ratio of approximately 1:1:3.5. Incubations of the microsomal preparations with both UDP-[14C]-GlcUA and UDP-GalN[3H]Ac together resulted in formation of [14C,3H]chondroitin chains added to the endogenous chondroitin sulfate. Degradation by chondroitinase ABC resulted in products with a molar ratio of [14C,3H]Di-OS to GalN[3H]Ac varying from approximately 1:1.5 to 1:3. The results of these experiments indicate that chondroitin 6-sulfate terminates at its nonreducing end in a mixture of GlcUA and GalNAc (some sulfated). GalNAc is somewhat more frequent as the terminal sugar and adds more readily to endogenous acceptors.

UI	MeSH Term	Description	Entries
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D002356	Cartilage	A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. There are three major types: HYALINE CARTILAGE; FIBROCARTILAGE; and ELASTIC CARTILAGE.	Cartilages
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick
D002807	Chondroitin	A mucopolysaccharide constituent of chondrin. (Grant & Hackh's Chemical Dictionary, 5th ed)
D002809	Chondroitin Sulfates	Derivatives of chondroitin which have a sulfate moiety esterified to the galactosamine moiety of chondroitin. Chondroitin sulfate A, or chondroitin 4-sulfate, and chondroitin sulfate C, or chondroitin 6-sulfate, have the sulfate esterified in the 4- and 6-positions, respectively. Chondroitin sulfate B (beta heparin; DERMATAN SULFATE) is a misnomer and this compound is not a true chondroitin sulfate.	Chondroitin 4-Sulfate,Chondroitin 6-Sulfate,Chondroitin Sulfate A,Chondroitin Sulfate C,Blutal,Chondroitin 4-Sulfate, Aluminum Salt,Chondroitin 4-Sulfate, Potassium Salt,Chondroitin 6-Sulfate, Potassium Salt,Chondroitin 6-Sulfate, Sodium Salt,Chondroitin Sulfate,Chondroitin Sulfate 4-Sulfate, Sodium Salt,Chondroitin Sulfate, Calcium Salt,Chondroitin Sulfate, Iron (+3) Salt,Chondroitin Sulfate, Iron Salt,Chondroitin Sulfate, Potassium Salt,Chondroitin Sulfate, Sodium Salt,Chondroitin Sulfate, Zinc Salt,Chonsurid,Sodium Chondroitin Sulfate,Translagen,Chondroitin 4 Sulfate,Chondroitin 4 Sulfate, Aluminum Salt,Chondroitin 4 Sulfate, Potassium Salt,Chondroitin 6 Sulfate,Chondroitin 6 Sulfate, Potassium Salt,Chondroitin 6 Sulfate, Sodium Salt,Chondroitin Sulfate 4 Sulfate, Sodium Salt,Chondroitin Sulfate, Sodium,Sulfate, Chondroitin,Sulfate, Sodium Chondroitin,Sulfates, Chondroitin
D004838	Epiphyses	The head of a long bone that is separated from the shaft by the epiphyseal plate until bone growth stops. At that time, the plate disappears and the head and shaft are united.	Epiphysis
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia