Spacer-modified trisaccharide glycosides that mimic the biantennary Asn-linked oligosaccharide acceptor of (1----4)-beta-D-galactosyltransferase and can be used as competitive inhibitors and for irreversible deactivation.
The biantennary spacer-modified trisaccharide glycoside methyl 3,6-di-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyloxyethyl)-alpha -D- mannopyranoside (5) was synthesised and used together with several 2-acylamino-2-deoxy-D-glucose derivatives in competition experiments with beta-D-galactosyltransferase. Compound 5 was an acceptor substrate (KM 0.18 mM) comparable to the biantennary core heptasaccharide of glycoproteins (KM 0.13 mM). Replacing the N-acetyl group by other N-acyl groups did not alter the kinetic parameters significantly. When the N-acyl group was iodoacetyl, the compound was an irreversible inhibitor.
Ats
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SC
Institut für Organische Chemie und Biochemie, Universität Freiburg, FRG.
Lehmann
J
J
Petry
S
S
D001216:Asparagine / Q000737:chemistry*; D001667:Binding, Competitive / Q000502:physiology; D002240:Carbohydrate Sequence; D005690:Galactose / Q000737:chemistry; D006027:Glycosides / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009844:Oligosaccharides / Q000737:chemistry*; D014312:Trisaccharides / Q000737:chemistry*; D006022:beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase / Q000037:antagonists & inhibitors / Q000737:chemistry*
D006027:Glycosides; D009844:Oligosaccharides; D014312:Trisaccharides; D001216:Asparagine; D006022:beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase; D005690:Galactose