Oligosaccharide synthesis enzymatic approach

Oligosaccharide syntheses employing enzymatic reactions would in principle greatly benefit from being performed on a polymer support since the support might effectively facilitate isolation of the final product. Presumably, a water-soluble polymeric support will be preferable to any insoluble support since reaction rates could otherwise become too slow. Glycosidases as synthetic enzymes would be the best candidates to study this type of the enzymic approach to oligosaccharide synthesis. 

Jahn M, Withers SG. New approaches to enzymatic oligosaccharide synthesis glycosynthases and thioglycoligases. Biocatal. Biotransform. 2003 21 159-166. 

Since the chemical synthesis of oligosaccharides requires many synthetic steps including protection and deprotection procedures, the enzymatic approach has attracted much attention for the rapid s)uithesis of oligosaccharides. In addition, the perfect regio- and stereoselectivities of enzymatic methods with glycosyltransferases are quite attractive. Several transferases such as 8(l,4)-galactosyltransferase, a(l,3)-fucosyltransferase, and a-sialyltransferase have been used for polymer-supported enzymatic synthesis [70,71,72,73,74,75]. The selection of the pol)uner support is very important for the pol)uner-supported enz)unatic synthesis of oligosaccharides. 

Karst NA, Linhardt RJ (2003) Recent chemical and enzymatic approaches to the synthesis of glycosaminoglycan oligosaccharides. CurrMed Chem 10 1993-2031 Yeung BKS, Chong PYC, Petillo PA (2002) Synthesis of glycosaminoglycans. J Carbohydr Chem 21 799-865... 

In conclusion, compared with solution-phase synthesis, solid-phase enzymatic synthesis, generally, needs higher concentrations of enzyme, longer reaction times, and a large excess of donors. Although there is still room for improvement in terms of yields and scale-up of syntheses, in solid-phase synthesis purification procedures are straightforward so it is expected that this approach will open the route to automated oligosaccharide synthesis in the near future. 

Chemical and enzymatic approaches to the synthesis of tyclic 165 oligosaccharides... 

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