74211-28-2Relevant academic research and scientific papers
Facile preparation of indoxyl- and nitrophenyl glycosides of lactosamine and isolactosamine
Boettcher, Stephan,Thiem, Joachim
, p. 10856 - 10861 (2014/03/21)
The synthesis of the novel indoxyl glycosides of N-acetyl-lactosamine (X-LacNAc) and N-acetyl-isolactosamine (X-LNB) is reported employing glycosyl chlorides in a facile phase transfer glycosylation, followed by mild decarboxylation and finally deacetylat
Glycosynthase with broad substrate specificity-an efficient biocatalyst for the construction of oligosaccharide library
Wei, Jinhua,Lv, Xun,Lue, Yang,Yang, Gangzhu,Fu, Lifeng,Yang, Liu,Wang, Jianjun,Gao, Jianhui,Cheng, Shuihong,Duan, Qian,Jin, Cheng,Li, Xuebing
, p. 2414 - 2419 (2013/05/23)
A versatile glycosynthase (TnG-E338A) with strikingly broad substrate scope has been developed from Thermus nonproteolyticus β-glycosidase (TnG) by using site-directed mutagenesis. The practical utility of this biocatalyst has been demonstrated by the facile generation of a small library containing various oligosaccharides and a steroidal glycoside (total 25 compounds) in up to 100 % isolated yield. Moreover, an array of eight gluco-oligosaccharides has been readily synthesized by the enzyme in a one-pot, parallel reaction, which highlights its potential in the combinatorial construction of a carbohydrate library that will assist glycomic and glycotherapeutic research. Significantly, the enzyme provides a means by which glycosynthase technology may be extended to combinatorial chemistry.
Accelerated enzymatic galactosylation of N -acetylglucosaminolipids in lipid microdomains
Noble, Gavin T.,Craven, Faye L.,Voglmeir, Josef,Sardzik, Robert,Flitsch, Sabine L.,Webb, Simon J.
supporting information; experimental part, p. 13010 - 13017 (2012/10/08)
A fluoro-tagged N-acetylglucosamine-capped glycolipid that can form lipid microdomains in fluid phospholipid bilayers has been shown to be enzymatically galactosylated by bovine β(1,4)-galactosyltransferase. MALDI MS, HPLC, and LC-MS revealed that the rate of enzymatic transformation was significantly enhanced by lipid clustering; at a 1% mol/mol loading, clustered glycolipids were galactosylated 9-fold faster than glycolipids dispersed across the bilayer surface. The transformation of the GlcNAc glycocalyx into a Gal(β1-4)GlcNAc glycocalyx relabeled these vesicles, making them susceptible to agglutination by Erythrina cristagalli lectin (ECL). The kinetic parameters for this transformation revealed a lower apparent K m when the substrate lipids were clustered, which is attributed to multivalent binding to an extended substrate cleft around the active site. These observations may have important implications where soluble enzymes act on substrates embedded within cellular lipid rafts.
Synthesis and utility of sulfated chromogenic carbohydrate model substrates for measuring activities of mucin-desulfating enzymes
Clinch, Keith,Evans, Gary B,Furneaux, Richard H,Rendle, Phillip M,Rhodes, Phillippa L,Roberton, Anthony M,Rosendale, Douglas I,Tyler, Peter C,Wright, Damian P
, p. 1095 - 1111 (2007/10/03)
A chromogenic substrate, 4-nitrophenyl 2-acetamido-2-deoxy-β-D-glucopyranoside 6-sodium sulfate was synthesized and used in combination with β-N-acetylhexosaminidase for detection of the sulfatase, MdsA, by release of 4-nitrophenol. MdsA was originally isolated from the bacterium Prevotella strain RS2 and is believed to be involved in desulfation of sulfomucins, major components of the mucus barrier protecting the human colon surface. The exo nature of the MdsA sulfatase was indicated by its inability to de-esterify the disaccharide 4-nitrophenyl β-D-galactopyranosyl-(1→4)-2-acetamido-2-deoxy-β-D- glucopyranoside 6-sodium sulfate. This latter compound was prepared from monosaccharide precursors by two different methods, the shorter requiring just six steps from 4-nitrophenyl 2-acetamido-2-deoxy-β-D-glucopyranoside and giving an overall yield of 26.4%. The syntheses of 4-nitrophenyl β-D-galactopyranoside 3-triethylammonium sulfate and 6-triethylammonium sulfate and their use in combination with β-galactosidase as chromogenic substrates for detecting Bacteroides fragilis sulfatases with different specificities was also demonstrated.
Enhanced enzymatic reactions in a microchannel reactor
Kanno, Kenichi,Kawazumi, Hirofumi,Miyazaki, Masaya,Maeda, Hideaki,Fujii, Masayuki
, p. 687 - 690 (2007/10/03)
Organic and enzymatic reactions in microchannel reactors were discussed. Hydrolytic activity of a microchannel pre-treated with enzyme solution was studied. It was found that the reaction rate in microchannel is much faster than the micro test tube. Mass transfer is also much more efficient in microchannel.
Efficient preparation of natural and synthetic galactosides with a recombinant β-1,4-galactosyltransferase-/UDP-4′-gal epimerase fusion protein
Blixt,Brown,Schur,Wakarchuk,Paulson
, p. 2442 - 2448 (2007/10/03)
The numerous biological roles of LacNAc-based oligosaccharides have led to an increased demand for these structures for biological studies. In this report, an efficient route for the synthesis of β-galactosides using a bacterial β-4-galactosyltransferase/-UDP-4′-gal-epimerase fusion protein is described. The lgtB gene from Neisseria meningitidis and the galE gene from Streptococcus thermophilus were fused and cloned into an expression vector pCW. The fusion protein transfers galactose to a variety of different glucose- and glucosamine-containing acceptors, and utilizes either UDP-galactose or UDP-glucose as donor substrates. A crude lysate from Escherichia coli expressing the fusion protein is demonstrated to be sufficient for the efficient preparation of galactosylated oligosaccharides from inexpensive UDP-glucose in a multigram scale. Lysates containing the fusion protein are also found to be useful in the production of more complex oligosaccharides in coupled reaction mixtures, e.g., in the preparation of sialosides from N-acetylglucosamine. Thus, bacterially expressed fusion protein is well suited for the facile and economic preparation of natural oligosaccharides and synthetic derivatives based on the lactosamine core.
A convenient synthesis of β-D-galactosyl disaccharide derivatives using the β-D-galactosidase from Bacillus circulans
Usui,Kubota,Ohi
, p. 315 - 323 (2007/10/02)
β-D-Gal-(1 → 4)-β-D-GlcNAc-OC6H4NO2-p (p-nitrophenyl N-acetyl-β-lactosaminide) and β-D-Gal-(1 → 6)-β-D-GlcNAc-OC6H4NO2-p (p-nitrophenyl N-acetyl-β-isolactosaminide) were regioselectively synthesized from lactose and p-nitrophenyl 2-acetamido-2-deoxy-glucopyranoside, employing transglycosylation by the β-D-galactosidase from Bacillus circulans and by controlling the concentration of organic solvent in the reaction system. The (1 → 4)-linked disaccharide was formed exclusively when the concentration of organic solvent was high, whereas the (1 → 6)-linked isomer was produced with a low concentration. Further utilization of the transglycosylation by the enzyme led to the regioselective formation of β-D-Gal-(1 → 4)-D-GalNAc and β-D-Gal-(1 → 4)-β-D-GalNAc-OC6H4NO2-p. With the enzyme, β-D-galactosyl transfer occurred preferentially at the O-4 position of GlcNAc and GalNAc, regardless of the configuration of the hydroxyl group. β-D-Gal-(1→4)-b-D-GlcNAc-OC6H4NO2-p (p-nitrophenyl N-acetyl-β-lactosaminide) and β-D-Gal-(1→6)-β-D-GlcNAc-OC6H4NO2-p (p-nitrophenyl N-acetyl-β-isolactosaminde) were regioselectively synthesized from lactose and p-nitrophenyl 2-acetamido-2-deoxy-glucopyranoside, employing transglycosylation by the b-D-galactosidas from Bacillus circulans and by controlling the concentration of organic solvent in the reaction system. The (1→4) linked disaccharide was formed exclusively when the concentration of organic solvent was high, whereas the (1→6)-linked isomer was produced with a low concentration. Further utilization of the transglycosylation by the enzyme led to the regioselective formation of β-D-Gal-(1→4)-D-GalNAc and β-D-Gal-(1→4)-β-D-GalNAc-OC6H4NO2-p. With the enzyme, β-D-galactosyl transfer occurred preferentially at the O-4 position of GlcNAc, regardless of the configuration of the hydroxyl group.
SYNTHESIS OF p-NITROPHENYL 2-ACETAMIDO-2-DEOXY-4-O-β-D-GALACTOPYRANOSYL-β-D-GLUCOPYRANOSIDE, AND p-NITROPHENYL 6-O-(2-ACETAMIDO-2-DEOXY-3-O- AND -4-O-β-D-GALCTOPYRANOSYL-β-D-GLUCOPYRANOSYL)-α-D-MANNOPYRANOSIDE
Rana, Surjit S.,Barlow, Joseph J.,Matta, Khushi L.
, p. 257 - 272 (2007/10/02)
A facile synthesis of p-nitrophenyl 2-acetamido-2-deoxy-4-O-β-D-galactopyranosyl-β-D-glucopyranoside was accomplished by saponification of the product obtained by reaction of 2-acetamido-3,6-di-O-acetyl-2-deoxy-4-O-(2,3,4,6-tetra-O-acetyl-β-D-galactopyran
