Glycosyl transferases specificity

As detailed structural information is obtained from a greater diversity of parasitic nematodes it is expected that the occurrence of stage-specific carbohydrate antigens, and therefore stage-specific glycosyl transferase activities, will be identified as a common characteristic. 

High selectivity and substrate specificity of glycosyl transferases make them valuable catalysts for special linkages in polymer-supported synthesis. There is, however, still a rather limited set of enzymes available to date, and the need to synthesize a variety of natural and non-natural oligosaccharides prevails. Particularly with regard to combinatorial approaches, chemical solid-phase oligosaccharide synthesis promises to meet the demands most effectively. 

The glycosyl transferases (E.C. 2.4 group) usually show high specificity towards the structure of the glycosyl acceptor. Furthermore, the enzyme specificity seems to determine which of the available nucleophilic acceptor-groups participates in the reaction, and also determines the stereospecificity of the glycosylation. 

Some glycosyl transferases show an unusual double substrate specificity that is, they strongly favor as substrates a pair of unrelated sugar nucleotides, such as adenosine and uridine derivatives.505... 

It thus seems more likely that the varied sulfatide profiles displayed by the testis of the animals listed in Table III will be explained by differing potentials, among species, of that organ to synthesize the lipid moieties, and by the specificities for both the lipid acceptors and the sugar donors of the glycosyl transferases involved in the second stage of sulfatide biosynthesis (cf.32). 

V Shibaev Biosynthesis of salmonella O-antigenic polysaccharide specificity of glycosyl transferases... 

Control of phase 3 of the synthesis is influenced by the specificities of the transferases, by the concentrations of substrates and acceptor molecules, and by allosteric effects and feedback-control mechanisms. In order that synthesis of the oligosaccharide chains shall be reproducible, each glycosyl transferase must be present at specific sites and at concentration levels sufficient to effect the addition of the... 

Although the use of glycosyl transferases require more expensive sugar nucleotides, the exquisite specificities offered by these enzymes sometimes override the cost concerns. Glyco-syltransferase often are used in terminal modifications such as... 

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