Galactosidase-Assisted Synthesis En Route to Type I And Type II Structures of Chitooligomers
作者:Ulrike Gambert、Harald S. Conradt、Manfred Nimtz、Joachim Thiem
DOI:10.1080/07328300008544103
日期:2000.1
Transgalactosylation of chitobiose and chitotriose led to formation of terminally (beta 1-3)- and (beta 1-4)-galactosylated chitooligosaccharides ready for fucosylation to give Lewis(a) and Lewis(x) motifs. Their structures could be assigned employing HPAEC-PAD, methylation, ESI-MS/MS and NMR analyses.
Enzymatic Galactosylation of Cello‐ and Chito‐Oligomers
作者:Harald Streicher、Oliver Scheel、Joachim Thiem
DOI:10.1080/07328300802030779
日期:2008.5
Terminal galactosylations of cello- and chito-oligomers are studied employing galactosyltransferase with and without alpha-lactalbumin. The lactose synthase complex allows just for galactosylation of cellobiose in lower yield but not for higher cello-oligomers. In contrast, the affinity in galactosylation of chito-oligomers increases with higher members to reach the maximum at chitohexaose with only a 30% reduction in transfer rate. In addition to kinetic data, preparative studies with a number of acceptor substrates gave galactosylated oligosaccharides in high yields.[GRAPHICS]
Galactosyltransferase from bovine milk was found to be able to utilise UDP-Glc to transfer Glc onto GlcNAc and chitooligomers [-beta-GlcNAc-(1-->4)-](n), n=2-4. beta-Glucosylated products were used in binding studies with NKR-P1A protein cloned from rat natural killer cells. (C) 1998 Elsevier Science Ltd.
Synthesis of Galactose-Terminated Oligosaccharides by Use of Galactosyltransferase
作者:Joachim Thiem、Torsten Wiemann
DOI:10.1055/s-1992-34174
日期:——
Galactosyltransferase catalyzes the galactosylation of oligosaccharides terminated by glucose and by 2-acetamido-2-deoxy glucopyranose, respectively. Variations concerning the acceptor substrate as well as the donor substrate are described.