75669-79-3Relevant academic research and scientific papers
Escherichia coli O86 O-antigen biosynthetic gene cluster and stepwise enzymatic synthesis of human blood group B antigen tetrasaccharide
Yi, Wen,Shao, Jun,Zhu, Lizhi,Li, Mei,Singh, Mamata,Lu, Yuquan,Lin, Steven,Li, Hanfen,Ryu, Kang,Shen, Jie,Guo, Hongjie,Yao, Qingjia,Bush, C. Allen,Wang, Peng G.
, p. 2040 - 2041 (2005)
Previous study showed that some Gram-negative bacteria possess human blood group activity. Among them, Escherichia coli O86 has high blood group B activity and weak blood group A activity. This is due to the cell surface O-antigen structure, which resembles that of human blood group B antigen. In this study, we sequenced the entire E. coli O86 antigen gene cluster and identified all the genes responsible for O-antigen biosynthesis by sequence comparative analysis. The blood group B-like antigen in E. coli O86 O-polysaccharide was synthesized by sequentially employing three glycosyltransferases identified in the gene cluster. More importantly, we identified a new bacterial glycosyltransferase (WbnI) equivalent to human blood group transferase B (GTB). The enzyme substrate specificity and stepwise enzymatic synthesis of blood group B-like antigen revealed that the biosynthetic pathway of B antigen is essentially the same in E. coli O86 as in humans. This new finding provides a model to study the specificity and structure relationship of blood group transferases and supports the hypothesis of anti-blood group antibody production by bacterial stimulation. Copyright
Subsequent enzymatic galactosylation and sialylation towards sialylated Thomsen-Friedenreich antigen components
Kroeger, Lars,Scudlo, Agnes,Thiem, Joachim
, p. 1217 - 1227 (2006)
Sialyloligosaccharides of the type Neu5 Acα2-3Galβ1-3GalNAc and a range of corresponding motifs play an important role in nature and are found in gangliosides, Lewis type I structures and the sialyl-Thomsen-Friedenreich antigen occurring in higher animals, viruses, bacteria, protozoa and pathogenic fungi. There is considerable interest to evaluate the significant functionalities of these glycostructures, and here we present a chemoenzymatic approach by a facile synthesis of such motifs. Employing chemoenzymatic methods, several modified Galβ1-3GalNAc derivatives were synthesized. Modifications were introduced at the stage of the monomeric building blocks prior to formation of the disaccharides by means of four different β-galactosidases from bovine testes, Bacillus circulans and Xanthomonas manihotis as well as the phosphorylase from Bifidobacterium bifidum. Finally, the modified disaccharide derivatives could be efficiently sialylated using the recombinant trans-sialidase from Trypanosoma cruzi.
Selective anomeric acetylation of unprotected sugars in water
Lim, David,Fairbanks, Antony J.
, p. 1896 - 1900 (2017/03/09)
High yielding selective acetylation of only the anomeric hydroxyl of unprotected sugars is possible in aqueous solution using 2-chloro-1,3-dimethylimidazolinium chloride (DMC), thioacetic acid, and a suitable base. The reaction, which may be performed on a multi-gram scale, is stereoselective for sugars that possess a hydroxyl group at position-2, exclusively yielding the 1,2-trans products. The use of an iterative reagent addition procedure allows the use of sodium carbonate as the base, avoiding the formation of triethylammonium salts, which may hamper product purification. The glycosyl acetate products may be used as donor substrates for glycosidase-catalysed synthesis. The crude aqueous acetylation reaction mixture may also be used for this purpose.
Facile one-step syntheses of modified O-glycoprotein Galβ1-3GalNAc structures by transglycosylation employing three β-galactosidases from bovine testes, Xanthomonas manihotis, and Bacillus circulans
Kroeger, Lars,Thiem, Joachim
, p. 717 - 722 (2007/10/03)
Natural O-glycoproteins such as the Thomsen-Friedenreich antigen or gangliosides contain the motif Galβ1-3GalNAc as an important disaccharide with significant biologic activity. The arrangement of spatial functionalities in this structure are of particular interest with regard to the development of potential leads en route to pharmaceuticals. Therefore, it was desired to obtain access to a range of modified derivatives of the aforementioned motif paying particular attention to introducing specific deoxy functions instead of hydroxyl groups. Copyright Taylor & Francis, Inc.
Synthesis and conformational analysis of the T-antigen disaccharide (β-D-Gal-(1←3)-α-D-GalNAc-OMe)
Bukowski, Ralph,Morris, Laura M.,Woods, Robert J.,Weimar, Thomas
, p. 2697 - 2705 (2007/10/03)
We report an improved synthesis of the T-antigen disaccharide [β-D-Gal-(1←3)-α-D-GalNAc-OMe], incorporating recycling of the undesired β-glycosyl acceptor [methyl 2-azido-4,6-benzylidene-2-deoxy-β-D-galactopyranoside (9β)] through anomerization by treatment with FeCl3. The conformational analysis of the disaccharide made use of high quality NOE data in combination with extensive Metropolis Monte-Carlo (MMC) and molecular dynamic (MD) simulations. To sample the conformational space sufficiently, 9.5·106 Monte-Carlo steps were collected for the MMC simulations, while the fully solvated MD simulations were performed for 10 ns for comparison. In general, the MMC and MD simulations agreed very well. Comparison of theoretical NOE curves from both MMC and MD simulations with the experimental curves showed that the disaccharide populates two regions of conformational space, with a population of about 95% for the global minimum energy region and about 5% for a local minimum energy region.
Characterization of the Immobilized β-Galactosidase C from Bacillus circulans and the Production of β(1→3)-linked Disaccharides
Naundorf, Andreas,Caussette, Mylene,Ajisaka, Katsumi
, p. 1313 - 1317 (2007/10/03)
A recombinant β-galactosidase, which was obtained from the β-galactosidase C gene of Bacillus circulans and cleaves the non-reducing end galactosyl residue of β(1→3)-linkages selectively, was immobilized using CNBr-Sepharose. Although the effect of pH was not changed by the immobilization, the thermostability and stability in the presence of DMF were increased. Optimization of the transglycosylation using para-nitrophenyl β-D-galactopyranoside as a donor and benzyl-α-D-N-acetylgalactosaminide as an acceptor afforded a β(1→3)-linked disaccharide derivative with 62% molar yield in a gram scale synthesis. Using the methyl-analogue as an acceptor, 53% of the acceptor was converted to the respective β(1→3)-disaccharide.
Stereoselective preparation of alkyl glycosides of 2-acetamido-2-deoxy-α-D-glucopyranose by nonclassical halide-ion catalysis and synthesis and NMR spectroscopy of α-D-Gal p-(1-->3)-α-D-Glc pNAc-OMe
Pozsgay, Vince,Coxon, Bruce
, p. 171 - 178 (2007/10/02)
Keywords: Alkyl glycosides; 2-Acetamido-2-deoxy-α-D-glucopyranose; α-D-Gal p-(1 --> 3)-α-d-GlcpNAcOMe
