Synthesis of 3″-deoxy and 4″-deoxy Lewisx trisaccharides is described.Phenyl 2,3,6-tri-O-benzoyl-4-deoxy-1-thio-β-Dxylo-hexopyranoside was condensed with a diol of glucosamine to give regio-and stereo-selectively a...Synthesis of 3″-deoxy and 4″-deoxy Lewisx trisaccharides is described.Phenyl 2,3,6-tri-O-benzoyl-4-deoxy-1-thio-β-Dxylo-hexopyranoside was condensed with a diol of glucosamine to give regio-and stereo-selectively a disaccharide.Stereose-lective fucosylation of this disaccharide provided a protected deoxy Lewisx trisaccharide which was deprotected to give the 4″-deoxy Lewisx trisaccharide.Application of the similar synthetic sequence provided the 3″-deoxy Lewisx trisaccharide.展开更多
The trisaccharide unit in lipopolysaccharide of Bordetella pertussis is important for immune recognition,but how the rare sugar 2-acetamido-4-methylamino-fucose in the trisaccharide unit is synthesized and transferred...The trisaccharide unit in lipopolysaccharide of Bordetella pertussis is important for immune recognition,but how the rare sugar 2-acetamido-4-methylamino-fucose in the trisaccharide unit is synthesized and transferred to the core of lipopolysaccharide in B.pertussis remains unclear.In this study,we demonstrated that the genes bplF,bplG,bplL and bplI are involved in the synthesis and transfer of 2-acetamido-4-methylamino-fucose to the core of lipopolysaccharide in B.pertussis.These genes were overexpressed with various combination in a recombinant E.coli strain which can synthesize B.pertussis corelipid A.Lipopolysaccharides were isolated from these strains and analyzed by using SDS-PAGE,ion chromatography and NMR.Based on these analyses,the mechanism of biosynthesis and transfer of 2-acetamido-4-methylamino-l-fucose to the core-lipid A in B.pertussis is proposed.展开更多
基金support from the CNRS and the UPMC-Paris 6 is gratefully acknowledged
文摘Synthesis of 3″-deoxy and 4″-deoxy Lewisx trisaccharides is described.Phenyl 2,3,6-tri-O-benzoyl-4-deoxy-1-thio-β-Dxylo-hexopyranoside was condensed with a diol of glucosamine to give regio-and stereo-selectively a disaccharide.Stereose-lective fucosylation of this disaccharide provided a protected deoxy Lewisx trisaccharide which was deprotected to give the 4″-deoxy Lewisx trisaccharide.Application of the similar synthetic sequence provided the 3″-deoxy Lewisx trisaccharide.
基金supported by the National Key Research and Development Program of China(2018YFA0900300)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(CX10295).
文摘The trisaccharide unit in lipopolysaccharide of Bordetella pertussis is important for immune recognition,but how the rare sugar 2-acetamido-4-methylamino-fucose in the trisaccharide unit is synthesized and transferred to the core of lipopolysaccharide in B.pertussis remains unclear.In this study,we demonstrated that the genes bplF,bplG,bplL and bplI are involved in the synthesis and transfer of 2-acetamido-4-methylamino-fucose to the core of lipopolysaccharide in B.pertussis.These genes were overexpressed with various combination in a recombinant E.coli strain which can synthesize B.pertussis corelipid A.Lipopolysaccharides were isolated from these strains and analyzed by using SDS-PAGE,ion chromatography and NMR.Based on these analyses,the mechanism of biosynthesis and transfer of 2-acetamido-4-methylamino-l-fucose to the core-lipid A in B.pertussis is proposed.
