Glycoconjugates engineering

In summary, for aU of the above-mentioned applications, the synthesis of carbohydrates and derivatives thereof is necessary to foster the field of glyco-engineering. Many procedures have been established to produce synthetic (neo)glycoconjugates by chemical or enzymatic methods and these are summarized in excellent reviews [12, 27, 28]. 

Liu C-J, Blount JW, Steele CL, Dixon RA. 2002. Bottlenecks for metabolic engineering of isoflavone glycoconjugates in Arabidopsis. Proc Natl Acad Sci USA 99 14578-14583. 

We begin with an overview of the structures of glycoconjugates on cell surfaces (for more comprehensive reviews, see Refs. 2, 12-14, and 24). Next, the pathways of monosaccharide interconversions inside the cell are smnmarized, providing a framework for opportunities in unnatural monosaccharide metabolism. Specihc examples of modihed sugars and their effects on cells are then presented. Finally, the biosynthetic pathway of sialic acid is discussed with respect to its utility for cell surface oligosaccharide engineering. 

Figure 44 Strategy for identifying the binding partners of sialosides. Metabolic engineering can be used to replace sialic acids with their photocross-linking counterparts. Modified glycoconjugates can be subjected to in situ irradiation to form cross-links with their binding partners. The covalently bound complexes can be isolated and analyzed by immunochemical or mass spectrometry methods.

Toda A, Yamada K, Nishimura S-I. An engineered biocatalyst for the synthesis of glycoconjugates utilization of (31,3-V-acetyl-D-glucosaminyltransferase from Streptococcus agalactiae type la expressed in Escherichia coli as a fusion with maltose-binding protein. Adv Synth Catal 2002 344 61-69. 

Synthesis of Glycoconjugates through Biosynthesis Pathway Engineering... 

In this chapter, we have summarized striking examples of cascade reactions for the chemo-enzymatic synthesis of glycoconjugates. The benefit of cascade reactions without intermediate product work-up is emerging in the field of glycan synthesis. Future studies should be therefore directed toward biocatalyst engineering and process design to match the requirements for sequential, one-pot, and convergent cascade reactions. 

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