Synthesis of Uridine 5′-(α-D-Fucopyranosyl Diphosphate) and (Digitoxigenin-3β-yl)-β-D-Fucopyranoside and Enzymatic β-D-Fucosylation of Cardenolide Aglycones in Digitalis lanata1
摘要:
The phosphorylation of 2,3,4-tri-O-acetyl-alpha-D-fucopyranose with o-phenylene phosphochloridate yielded alpha-D-fucopyranosyl phosphate which was used for condensation with uridine 5'-monophosphomorpholidate to give uridine 5'-(alpha-D-fucopyranosyl diphosphate) (UDP-alpha-D-fucose). A crude enzyme preparation from young leaves of Digitalis lanata EHRH has been shown to catalyze the transfer of D-fucose from synthetic UDP-alpha-D-fucose to cardenolide aglycones, such as digitoxigenin. The reaction product was identified and characterized by chemical synthesis, HPLC, and spectral methods as the 3 beta-O-beta-D-fucopyranoside of digitoxigenin (digiproside). (C) 1994 Academic Press, Inc.
Studies on the Substrate Specificity of <i>Escherichia coli</i> Galactokinase
作者:Jie Yang、Xun Fu、Qiang Jia、Jie Shen、John B. Biggins、Jiqing Jiang、Jingjing Zhao、Joshua J. Schmidt、Peng G. Wang、Jon S. Thorson
DOI:10.1021/ol034642d
日期:2003.6.1
rapidly synthesize sugar phosphates. Compared with chemical synthesis, enzymatic (kinase) routes to sugar phosphates would be attractive for this application. This work focuses upon the development of a high-throughput colorimetric galactokinase (GalK) assay and its application toward probing the substrate specificity and kineticparameters of Escherichia coli GalK. The demonstrated dinitrosalicylic
作者:Zhong-Rui Li、Ruofan Li、Laura Pasternack、Pengxi Chen、Chi-Huey Wong
DOI:10.1021/acs.joc.3c00553
日期:2023.6.2
Keto sugarnucleotides (KSNs) are common and versatile precursors to various deoxy sugarnucleotides, which are substrates for the corresponding glycosyltransferases involved in the biosynthesis of glycoproteins, glycolipids, and natural products. However, there has been no KSN synthesized chemically due to the inherent instability. Herein, the first chemical synthesis of the archetypal KSN TDP-4-
Präparat zur Wirkstoffapplikation in Kleinsttröpfchenform
申请人:Cevc, Gregor, Prof. Dr.
公开号:EP0475160A1
公开(公告)日:1992-03-18
Die Erfindung betrifft ein Präparat zur Applikation von Wirkstoffen in Form kleinster, insbesondere mit einer membranartigen Hülle aus einer oder wenigen Lagen amphiphiler Moleküle bzw. mit einer amphiphilen Trägersubstanz versehenen Flüssigkeitströpfchen, insbesondere zum Transport des Wirkstoffes in und durch natürliche Barrieren und Konstriktionen wie Häute und dergleichen. Das Präparat weist einen Gehalt einer randaktiven Substanz auf, der bis zu 99 Mol.-% des Gehaltes dieser Substanz entspricht, durch den der Solubilisierungspunkt der Tröpfchen erreicht wird. Das Präparat eignet sich zur nichtinvasiven Verabreichung von Antidiabetica, insbesondere von Insulin. Die Erfindung betrifft außerdem ein Verfahren zur Herstellung solcher Präparate.
Verfahren zur stereoselektiven Herstellung von beta-Fucopyranosylphosphaten und sehr reiner GDP-Fucose
申请人:MERCK PATENT GmbH
公开号:EP0502298A2
公开(公告)日:1992-09-09
Die Erfindung betrifft ein Verfahren zur stereoselektiven Herstellung von β-L-Fucopyranosyl-phosphaten über die Trichloracetimidate der geschützten L-Fucose und die Synthese und Aufreinigung von sehr reiner GDP-Fucose aus den β-L-Fucopyranosyl-phosphaten.
A highly efficient galactokinase from Bifidobacterium infantis with broad substrate specificity
作者:Lei Li、Yonghui Liu、Wenjun Wang、Jiansong Cheng、Wei Zhao、Peng Wang
DOI:10.1016/j.carres.2012.04.022
日期:2012.7
Galactokinase (GalK), particularly GalK from Escherichia coli, has been widely employed for the synthesis of sugar-1-phosphates. In this study, a GalK from Bifidobacterium infantis ATCC 15697 (BiGalK) was cloned and over-expressed with a yield of over 80 mg/L cell cultures. The k(cat)/K-m value of recombinant BiGalK toward galactose (164 s (1) mM (1) ) is 296 times higher than that of GalK from E. coli, indicating that BiGalK is much more efficient in the phosphorylation of galactose. The enzyme also exhibits activity toward galacturonic acid, which has never been observed on other wild type GalKs. Further activity assays showed that BiGalK has broad substrate specificity toward both sugars and phosphate donors. These features make BiGalK an attractive candidate for the large scale preparation of galactose-1-phosphate and derivatives. (C) 2012 Elsevier Ltd. All rights reserved.