Enzymatic glycosylations

Under certain conditions glucose molecules can induce free-radical production (see section on non-enzymatic glycosylation of protein). 

Non-enzymatic glycosylation Polyol pathway Reduced antioxidant resen/e Activated neutrophils, etc. 

Figure 13.28 Enzymatic glycosylation to prepare novel glycopeptides...

NMR, protein structure determination, 23, 275 non-enzymatic glycosylation, 14, 261 non-HIV antiviral agents, 36, 119, 38, 213 non-nutritive, sweeteners, V7, 323 non-peptide agonists, 32, 277 non-peptidic d-opinoid agonists, 37,159... 

Martearena, M. R., Blanco, S. and Ellenrieder, G. (2003). Synthesis of alkyl-alpha-L-rhamnosides by water soluble alcohols enzymatic glycosylation. Bioresource Technology 90 297-303. 

Strategy 1 Chemical (R = protecting group) or enzymatic glycosylation (R = H) of peptide or glycopeptide ... 

Scheme 14.1 Strategies for glycopeptide library synthesis Strategy 1 chemical or enzymatic glycosylation of peptide or glycopeptide Strategy 2 the building-block approach. While enzymes have not yet been used in the solid-phase synthesis of glycopeptide libraries, several resin-bound glycopeptides have been glycosylated enzymatically.36,114...

Scheme 7.7 Immobilization of a thiol-group containing sugar substrate on a hexavalent PEC-derivative for sulfatation and enzymatic glycosylation reactions.

Maillard reaction. The Maillard reaction is also known as non-enzymatic browning, non-enzymatic glycosylation, and glycation. It comprises the spontaneous reaction between carbonyl and amino compounds, such as sugars and proteins, respectively. It is especially well-known in the... 

The enzymatic glycosylation of natural products can be performed in principle by glycosidases, glycosyltransferases, and some other glycoside-processing enzymes -sometimes called transglycosidases. 

Experiments of site-specific mutagenesis were also carried out, leading, after enzymatic glycosylation, to unnatural erythromycin D and analogues (Khosla 1997). 

Zimowski J (1996) Enzymatic glycosylation of tomatidine in tomato plants. In Waller GR, Yamasaki K (eds) Saponins used in traditional and modern medicine. Plenum Press, New York,p 71... 

Fig. 2.2.5.4 Synthetic trisaccharides containing KDN and other NeuSAc derivatives prepared by enzymatic glycosyl transfer.

Thorson JS, Hosted TJ, Jiang J et al (2001) Nature s carbohydrate chemists the enzymatic glycosylation of bioactive bacterial metabolites. Curr Org Chem 5 139-167... 

Fig. 8. Enzymatic glycosylation in the solid-phase synthesis of oligosaccharides elongation of the glycopeptide with /M, 4-galactosyltrans-ferase and a-2,3-sialyltransferase. The glycopeptide is finally released by cleavage with a-chymotrypsin.

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