Glucosamine biochemistry

Not much has been added to the biochemistry of STRs in the recent years. Therefore, we will only briefly treat the biosynthetic pathway here. Biosynthesis of the aminocyclitol (streptidine) and 6-deoxyhexose (streptose) moieties are well understood, with some remaining gaps in the enzymology. Much less is known about the residual biosynthetic phases, the formation of A-methyl-L-glucosamine, the condensation of subunits, and the late modification steps potentially coupled with export. ... 

Montero-Moran GM, Lara-Gonzalez S, Alvarez-Anorve LI et al (2001) On the multiple functional roles of the active site histidine in catalysis and allosteric regulation of Escherichia coli glucosamine 6-phosphate deaminase. Biochemistry 40 10187-10196... 

Mucopolysaccharides are some of the most common structural carbohydrates in cestodes, although little is known of their biochemistry or function. They are heteropolymers and contain amino sugars (e.g. glucosamine, galactosamine) and uronic (glucuronic, galacturonic) acids. Often, mucopolysaccharides are complexed with proteins to form mucoproteins or glycoproteins, which, as discussed in Chapter 2, are major components of... 

Fig. 9. Structures of the various GPI anchors derived from experiments described in Section VI. The calculated masses include the C-terminal peptide, and can be directly correlated with the masses shown in Figure 5. Man, mannose Gal, galactose GalNAc, N-acetyl galactosamine GlcNH2, glucosamine Ino, inositol Sia, sialic acid. (Reproduced with permission from Stahl, N. et al. [1999]. Biochemistry 31, 5043-5053. Copyright American Chemical Society.)...

Asteriou, T., Deschrevel, B., Delpeeh, B., Bertrand, R, Bultelle, R, Merai, C., and Vincent, J. C. (2001). An improved assay for the N-acetyl-D-glucosamine redusing ends of polysaccharides in the presence of proteins. Analytical Biochemistry 293, 53-59. 

L. Garcia-Bunuel, M. Golden, and Y. Balfour Incorporation of radioactivity of D-glucosamine-l-C, D-glucose-l-C S D-galactose-l-C, and DL-serine-3-C into rat brain glycolipids. Biochemistry 2, 580 (1963). 

It is still not clear what the actions are of ehondroitin sulfate when taken as a nutritional supplement. Purported effects are the promotion and maintenanee of the structure and function of cartilage in the joints of the body. It has also been reported that chondroitin sulfate has anti-inflammatory and pain rehef effects. The biochemistry has been known for some time. Chondroitin sulfate is a GAG, previously described in the glucosamine mechanisms. It is essential for the structure and function of articular cartilage and provides the same properties as hyaluronic acid. While intra-articular injections of hyaluronic acid have been shown to relieve joint pain and improve mobihty, the same has not yet been demonstrated for chondroitin sulfate. It is speculated that oral ingestion of chondroitin sulfate may lead to an increase in hyaluronic acid. Thus, cartilage breakdown would be inhibited. ... 

Amino Sugars are formed formally by the replacement of a hydroxyl group with an amino group. In biochemistry three such compounds are important glucosamine (chitosamine), galactosamine (chondrosamine) and neuraminic acid. 

Molnar, J., 1967, Glycoproteins of Ehrlich ascites carcinoma cells. Incorporation of ( C)glucosamine and ( C)sialic acid into membrane proteins. Biochemistry 6 3064-3075. 

Wu, H. C., Meezan, E., Black, P. H., and Robbins, P. W., 1969, Comparative studies on the carbohydrate-containing membrane components of normal and virus-transformed mouse fibroblasts. I. Glucosamine-labeling patterns in 3T3, spontaneously transformed 3T3, and SV-40-transformed 3T3 cells. Biochemistry 8 2509-2517. 

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