Leloir-glycosyltransferases

Scheme 2.2.6.1 The reversible reaction of the Leloir glycosyltransferase sucrose synthase (EC 2.4.1.13) 1 sucrose 2 UDP-Gic 3 D-fructose.

The application of Leloir glycosyltransferases in glycoconjugate synthesis generally offers two advantages high product yields (up to 100%) and absolute stereo- and regioselectivity. 

Table 3. Recombinant mammalian Leloir-glycosyltransferases expressed in the mU to U scale3...

Sucrose synthase (SuSy) represents a unique plant Leloir glycosyltransferase as it catalyzes a freely reversible reaction in vivo and in vitro (Eq. 1) [349]. 

Seibel J, Beine R, Moraru R, Behringer C, Buchholz K (2006) A new pathway for the synthesis of oligosaccharides by the use of non-Leloir glycosyltransferases. Biocatal Bio-trans 24 157-165... 

Some transferases can directly use and transform oligosaccharides as donors without further activation. The following paragraph will discuss some reactions with non-Leloir glycosyltransferases which are performed on a preparative level. For example, cyclodextrin-al-4-glucosyltransferase (CGT) from Klebsiella pneumonia or from Bacillus macerans are rather versatile enzymes which can catalyze various reactions. 

This chapter reviews the literature on enzymatic synthesis utilizing Leloir glycosyltransferases, with focus on galactosyltransferases, fucosyltransferases, and sia-lyltransferases, most of which are commercially available or widely accessible. Also, they are well studied in terms of their donor and acceptor specificity and have been used for the synthesis of both natural oligosaccharides and their analogs. As well, two practical examples for the synthesis of trisaccharide analogs are given. 

Non-Leloir Glycosyltransferases Transfer of Glycosyl donors from Glycosyl Phosphates and Glycosides... 

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