Synthesis and enzymatic evaluation of modified acceptors of recombinant blood group A and B glycosyltransferases.
The disaccharide alpha-L-Fucp-(1 --> 2)-beta-D-Galp-(1 --> O)-Octyl (1) is an acceptor for the human blood group A and B glycosyltransferases. Seven analogues of 1, containing deoxy, methoxy and arabino modifications of the Fuc residue, were chemically synthesized and kinetically evaluated in radioactive enzymatic assays. Both the enzymes tolerate modification of the 3'-OH on the fucose residue. The 2'-OH was found to be key to the recognition of the acceptors by these enzymes. The arabino derivative was recognized as an acceptor by the A transferase (Km of 200 microM), but not the B transferase and is the first synthetic acceptor capable of distinguishing between the two enzyme activities.
Department of Chemistry, University of Alberta, Edmonton, AB, Canada T6G 2G2.
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Mukherjee
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Palcic
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Hindsgaul
D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D005700:Galactosyltransferases / Q000037:antagonists & inhibitors / Q000737:chemistry*; D006801:Humans; D008969:Molecular Sequence Data; D017350:N-Acetylgalactosaminyltransferases / Q000037:antagonists & inhibitors / Q000737:chemistry*; D011994:Recombinant Proteins / Q000138:chemical synthesis / Q000737:chemistry; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
D004187:Disaccharides; D011994:Recombinant Proteins; D005700:Galactosyltransferases; D017350:N-Acetylgalactosaminyltransferases; C003742:UDPgalactosamine-galactose acetylgalactosaminyltransferase; C023155:blood-group-substance alpha-D-galactosyltransferase