Chemical synthesis and kinetic characterization of UDP-2-deoxy-D-lyxo-hexose("UDP-2-deoxy-D-galactose"), a donor-substrate for beta-(1-->4)-D-galactosyltransferase.
Bovine beta-(1-->4)-galactosyltransferase (GalT) transfers galactose from UDP-galactose to beta-D-GlcpNAc-terminating oligosaccharides to produce N-acetyllactosamine sequences. We report here the chemical synthesis, structural characterization and enzymatic evaluation of the very labile UDP-2-deoxy-D-lyxo-hexose ("UDP-2-deoxy-galactose," 2) as an alternate donor for GalT. Donor 2 had kinetic parameters, including a Km value of 51 microM, almost identical to those for the natural substrate UDP-galactose when beta-D-GlcpNAc-O(CH2)8COOMe was used as the acceptor. The product of the enzymatic transfer was isolated and confirmed to have the expected 2'-deoxy-N-acetyllactosamine sequence.
Srivastava
G
G
Department of Chemistry, University of Alberta, Edmonton, Canada.
Hindsgaul
O
O
Palcic
M M
MM
D000818:Animals; D002417:Cattle; D007202:Indicators and Reagents; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D009237:N-Acetyllactosamine Synthase / Q000378:metabolism*; D013379:Substrate Specificity; D014531:Uridine Diphosphate Galactose / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism
D007202:Indicators and Reagents; C082837:UDP-2-deoxygalactose; D014531:Uridine Diphosphate Galactose; D009237:N-Acetyllactosamine Synthase