Synthesis of a library of xylogluco-oligosaccharides for active-site mapping of xyloglucan endo-transglycosylase
2006 (English)In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 71, no 14, 5151-5161 p.Article in journal (Refereed) Published
[GRAPHICS] Complex oligosaccharides containing R-D-xylosyl-(1 -> 6)-beta-D-glucosyl residues and unsubstituted beta-(1 -> 4)-linked D-glucosyl units were readily synthesized using enzymatic coupling catalyzed by the Cel7B E197A glycosynthase from Humicola insolens. Constituting this library required four key steps: ( 1) preparing unprotected building blocks by chemical synthesis or enzymatic degradation of xyloglucan polymers; (2) generating the donor synthon in the enzymatic coupling by temporarily introducing a lactosyl motif on the 4-OH of the terminal glucosyl units of the xylogluco-oligosaccharides; ( 3) synthesizing the corresponding R-fluorides, followed by their de-O-acetylation and the glycosynthase-catalyzed condensation of these donors onto various acceptors; and (4) enzymatically releasing lactose or galactose from the reaction product, affording the target molecules in good overall yields. These complex oligosaccharides proved useful for mapping the active site of a key enzyme in plant cell wall biosynthesis and modification: the xyloglucan endo-transglycosylase (XET). We also report some preliminary enzymatic results regarding the efficiency of these compounds.
Place, publisher, year, edition, pages
2006. Vol. 71, no 14, 5151-5161 p.
cell-wall enzymes, expression analysis, cellulose surfaces, mutant cellulase, hybrid aspen, endotransglycosylase, substrate, seeds, polysaccharides, purification
IdentifiersURN: urn:nbn:se:kth:diva-15796DOI: 10.1021/jo0525682ISI: 000238665500010ScopusID: 2-s2.0-33745728300OAI: oai:DiVA.org:kth-15796DiVA: diva2:333838
QC 201005252010-08-052010-08-05Bibliographically approved