Glycosaminoglycans biosynthesis

Biosynthesis and degradation of glycosaminoglycans biosynthesis of collagen, mineralization and demineralization of bone. Fatty acid synthesis and triglyceride storage in adipocytes promoted by insulin and triglyceride hydrolysis and fatty acid release stimulated by glucagon and adrenaline (epinephrine). 

The potentiating effects of 124 maybe related to an effect on cell volume and glycosaminoglycan biosynthesis, as previously proposed for the effects of 122 on B16 melanoma cells, whereas the czs-isomer 123 may selectively cause normalization of developing blood vessels in the primary tumor and thus inhibits metastases, Eq. (49) [165]. 

The effect of the base used for the condensation of xylose (7) with pentane-2,4-dione (1) was carefully examined. The best results were obtained using NaOH since 54 was obtained in 45 min at 50°C in 97% yield. Reduction of 54 gave 60, an activator of glycosaminoglycans biosynthesis, launched on the market in cosmetic skincare products as Pro-Xylane by L Oreal in 2006 [116, 117] (Fig. 10). 

Fig. 10 Structure of Pro-Xylane , an activator of glycosaminoglycans biosynthesis (L Oreal)...

Fig. 33.34. The synthesis of 3 -phosphoadenosine 5 -phosphosulfate (PAPS), an active sulfate donor. PAPS donates sulfate groups to cerebrosides to form sulfatides and is also involved in glycosaminoglycan biosynthesis (see Chapter 49). Ad = adenosine.

Kusche-Gullberg M, Kjellen L. Sulfotransferases in glycosaminoglycan biosynthesis. Curr Opin Struct Biol 2003 13 605-611. 

For rat epiphysial cartilage, the monosaccharide nucleotides and other intermediates (H8) in glycosaminoglycan biosynthesis have been isolated and quantitated. Collation of many of the data on the biosynthetic initiation and propagation of glycosaminoglycan chains has permitted the presentation of an overall scheme (K ), which is given in Section 4.3, p. 30. 

T6) is contradictory to this supposition in that it was deduced that vitamin A deficiency has no effect upon the biosynthesis of sulfated glycosaminoglycans, but that it does increase their turnover rate. From this it was concluded that vitamin A is not necessary for ycosaminogly-can chain biosynthesis. Excess of vitamin A increases the incorporation of [ S]sulfate (Bll). The effects of various derivatives of vitamin A have also been investigated (T6), and citral, a terpene structurally related to vitamin A, also affects glycosaminoglycan biosynthesis (B27). 

The dolichol-linked D-mannosyl, D-glucosyl, and 2-acetamido-2-deoxy-D-glucosyl residues are used in the glycosylation of proteins and in the biosynthesis of D-m an nan.2,35 GlcNAc-PP-Dol may also play a role in the synthesis of glycosaminoglycans. Reaction 4 is the first step in the formation of lipid-linked precursors for cellulose.46... 

Lee, C. R., Grodzinsky, A. J., and Pector, M. (2001). The effects of cross-linking of collagen-glycosaminoglycan scaffolds on compressive stiffness, chondrocyte-mediated contraction, proliferation and biosynthesis. Biomaterials 22,3145-3154. 

It seems probable that other L-hexuronic acids listed in Table III, such as L-iduronic,208 2-amino-2-deoxy-L-altruronic,209 and 2,3-diamino-2,3-dideoxy-L-guluronic210 acids may arise in bacterial polymers as a result of epimerization at C-5 at the polymer level. Such a pathway was demonstrated for the biosynthesis of L-idosyluronic acid residues in glycosaminoglycans of higher animals.211 212... 

Sugahara K, Kitagawa H. Recent advances in the smdy of the biosynthesis and functions of sulfated glycosaminoglycans. Curr. Opin. Struct. Biol. 2000 10 518-527. 

Here, we delineate the biosynthetic pathways of the most common types of protein glycosylation occurring in the secretory pathway mucin-type O-linked glycosylation, A-linked glycosylation, and the formation of glycosaminoglycans. In addition, we will briefly visit the biosynthesis of some less-common varieties of protein glycosylation. 

Figure 5 Biosynthesis and structure of glycosaminoglycans. Synthesis u GlcAT-l. The repeating disaccharides of heparin/HS, CS, and DS are shown.

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