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Yuriy A. Knirel - One of the best experts on this subject based on the ideXlab platform.

  • the unique structure of Bacterial Polysaccharides immunochemical studies on the o antigen of proteus penneri 4034 85 clinical strain classified into a new o83 proteus serogroup
    International Journal of Biological Macromolecules, 2020
    Co-Authors: Malgorzata Siwinska, Antoni Rozalski, Olga G Ovchinnikova, Agnieszka Zablotni, Evgeniya A Levina, Yuriy A. Knirel
    Abstract:

    Abstract The serological classification scheme of the opportunistic Proteus bacilli includes a number of Proteus penneri strains. The tested P. penneri 4034-85 strain turned out to be serologically distinguished in ELISA and Western blotting. The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of this strain and studied by sugar and methylation analyses and dephosphorylation along with 1H and 13C NMR spectroscopy, including 2D 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, HMBC, and HSQC-TOCSY experiments, The O-polysaccharide was found to have a linear repeating unit containing glycerol 1-phosphate and two residues each of Gal and GlcNAc. The following O-polysaccharide structure was established, which, to our knowledge, is unique among known Bacterial polysaccharide structures: →4)-β- d -GlcpNAc-(1→3)-α- d -Galp-(1→3)-β- d -GlcpNAc-(1→2)-β- d -Galp-(1→3)-Gro-1-P-(O→.

  • human antibodies eluted from ligand free sepharose capable of binding Bacterial Polysaccharides and sulfated glycans
    Molecular Immunology, 2019
    Co-Authors: Kira Dobrochaeva, Yuriy A. Knirel, Nailya Khasbiullina, Nadezhda Shilova, Polina Obukhova, Yu A Nokel, Nicolai V Bovin
    Abstract:

    Abstract Sepharose matrix without immobilized ligands binds antibodies from human blood serum or immunoglobulin preparations. The eluted antibodies bind Bacterial Polysaccharides having no structural similarity to agarose (Sepharose is a cross-linked polysaccharide agarose) with a high affinity. It is concluded that the identified antibodies are capable of recognizing spatial rather than linear epitopes of Bacterial Polysaccharides. This side activity of Sepharose matrix should be taken into account in isolating target antibodies and other proteins from human blood.

  • structure and genetics of the o specific polysaccharide of escherichia coli o27
    Carbohydrate Research, 2018
    Co-Authors: Andrei V. Perepelov, Sof'ya N. Senchenkova, Bin Liu, Tingting Chen, Andrei V Filatov, Jingjie Song, Yuriy A. Knirel
    Abstract:

    Abstract The O-specific polysaccharide (O-antigen) is a part of the lipopolysaccharide on the cell surface of Gram-negative bacteria. The O-polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of Escherichia coli O27 and studied by sugar analysis and Smith degradation along with 1H and 13C NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established, which is unique among known structures of Bacterial Polysaccharides: Download : Download high-res image (70KB) Download : Download full-size image where GlcA is non-stoichiometrically O-acetylated at position 3 (∼22%) or 4 (∼37%). Functions of genes in the O-antigen gene cluster of E. coli O27 were tentatively assigned by comparison with sequences in the available databases and found to be consistent with the O-polysaccharide structure.

  • Structure of the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) containing a 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose moiety.
    Journal of Natural Products, 2012
    Co-Authors: Anna N. Kondakova, Nikolay P Arbatsky, Marina S. Drutskaya, Sergei A. Nedospasov, Kseniya A. Novototskaya-vlasova, V. A. Shcherbakova, David Gilichinsky, Yuriy A. Knirel
    Abstract:

    A novel constituent of Bacterial Polysaccharides, 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose, was found in the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) and identified by 1D and 2D (1)H and (13)C NMR studies of the polysaccharide and a disaccharide obtained by solvolysis of the polysaccharide with triflic acid. The following structure of the branched polysaccharide was established by sugar analysis, triflic acid solvolysis, Smith degradation, and 2D NMR spectroscopy.

  • structure of the o polysaccharide of azorhizobium caulinodans hambi 216 identification of 3 c methyl d rhamnose as a component of Bacterial Polysaccharides
    Carbohydrate Research, 2012
    Co-Authors: Evelina L Zdorovenko, Yuriy A. Knirel, Olga A Valueva, Vadim V Kachala, Alexander S Shashkov, Iwona Komaniecka, Adam Choma
    Abstract:

    Abstract The O-polysaccharide was obtained from the lipopolysaccharide of the stem-nodulating nitrogen-fixing bacterium Azorhizobium caulinodans HAMBI 216 and studied by sugar and methylation analyses along with 1 H and 13 C NMR spectroscopy. The polysaccharide was found to have a linear pentasaccharide repeating unit containing d -rhamnose and its rarely occurring 2- O -methyl (Rha2 O Me) and 3- C -methyl (Rha3 C Me) derivatives and having the following structure: →3)-α- d -Rha p 2 O Me-(1→2)-β- d -Rha p 3 C Me-(1→3)-α- d -Rha p -(1→2)-β- d -Rha p 3 C Me-(1→3)-α- d -Rha p -(1→

Antoni Rozalski - One of the best experts on this subject based on the ideXlab platform.

  • the unique structure of Bacterial Polysaccharides immunochemical studies on the o antigen of proteus penneri 4034 85 clinical strain classified into a new o83 proteus serogroup
    International Journal of Biological Macromolecules, 2020
    Co-Authors: Malgorzata Siwinska, Antoni Rozalski, Olga G Ovchinnikova, Agnieszka Zablotni, Evgeniya A Levina, Yuriy A. Knirel
    Abstract:

    Abstract The serological classification scheme of the opportunistic Proteus bacilli includes a number of Proteus penneri strains. The tested P. penneri 4034-85 strain turned out to be serologically distinguished in ELISA and Western blotting. The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of this strain and studied by sugar and methylation analyses and dephosphorylation along with 1H and 13C NMR spectroscopy, including 2D 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, HMBC, and HSQC-TOCSY experiments, The O-polysaccharide was found to have a linear repeating unit containing glycerol 1-phosphate and two residues each of Gal and GlcNAc. The following O-polysaccharide structure was established, which, to our knowledge, is unique among known Bacterial polysaccharide structures: →4)-β- d -GlcpNAc-(1→3)-α- d -Galp-(1→3)-β- d -GlcpNAc-(1→2)-β- d -Galp-(1→3)-Gro-1-P-(O→.

  • structure of the o polysaccharide of providencia alcalifaciens o22 containing d glyceramide 2 phosphate
    European Journal of Organic Chemistry, 2012
    Co-Authors: Olga G Ovchinnikova, Antoni Rozalski, Nina A. Kocharova, Magdalena Bialczakkokot, Yuriy A. Knirel
    Abstract:

    O-Polysaccharides (O-antigens) are highly diverse glycopolymers present on the cell surface of Gram-negative bacteria, including the human opportunistic pathogen Providencia alcalifaciens. They define serospecificity of strains and are used for the serotyping of bacteria. In this work, a phosphorylated O-polysaccharide was isolated from P. alcalifaciens O22 and analyzed by chemical methods, ESI-MS, and 1H, 13C, and 31P NMR spectroscopy. It was found to contain two unusual components, 2-acetamido-4-amino-2,4,6-trideoxy-D-galactose (D-FucNAc4N) and D-glyceramide 2-phosphate (D-GroAN-2-P), the latter being identified for the first time in Bacterial Polysaccharides. The structure of the trisaccharide repeating unit of the O-polysaccharide was established to be 4)-(D-GroAN-2-P-3-)--D-GalNAc-(14)--D-Gal-(13)--D-FucNAc4N-(1.

  • elucidation of the full o polysaccharide structure and identification of the core type of the lipopolysaccharide of providencia alcalifaciens o9
    Carbohydrate Research, 2011
    Co-Authors: Olga G Ovchinnikova, Antoni Rozalski, Nina A. Kocharova, Nikolay P Arbatsky, Yuriy A. Knirel
    Abstract:

    Abstract Opportunistic human pathogens of the genus Providencia from the family Enterobacteriaceae are serotyped by their O-antigens, which represent the O-polysaccharide chains of the lipoPolysaccharides (LPSs) on the cell surface. In this work, the O-polysaccharide of Providencia alcalifaciens O9 was obtained by mild acid degradation of a long-chain S-form LPS. The structure of the hexasaccharide repeat (O-unit) of the O-polysaccharide containing one d -Gal, two d -Glc, and three d -GalNAc residues was established by sugar and methylation analyses along with one- and two-dimensional 1 H and 13 C NMR spectroscopy. Another degradation product was derived from a short-chain SR-form LPS and found to consist of a core oligosaccharide bearing one O-unit. Its studies by NMR spectroscopy and electrospray ionization mass spectrometry enabled identification of one of the GalNAc residues as the first monosaccharide of the O-unit, whose glycosidic linkage links the O-units to each other and the first O-unit to the core. The core is distinguished by the occurrence of two glycoforms differing in the nature of a lateral monosaccharide, which is either d -Glc or d -GlcNAc. Although composed of common monosaccharides, the O-polysaccharide of P. alcalifaciens O9 has a unique structure among Bacterial Polysaccharides, whereas the oligosaccharide region belongs to one of several core types recognized in the LPSs of Providencia .

  • The O-polysaccharide from the lipopolysaccharide of Providencia stuartii O44 contains L-quinovose, a 6-deoxy sugar rarely occurring in Bacterial Polysaccharides.
    Carbohydrate research, 2005
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Olga G Ovchinnikova, Alexander S Shashkov, F. V. Toukach, Agnieszka Torzewska, Antoni Rozalski
    Abstract:

    The O-polysaccharide (O-antigen) of Providencia stuartii O44:H4 (strain 3768/51) was obtained by mild acid degradation of the lipopolysaccharide and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, and H-detected (1)H,(13)C HSQC, and HMQC-TOCSY experiments. The O-polysaccharide was found to have a branched hexasaccharide repeating unit of the following structure: [Formula: see text].

  • structure of the o polysaccharide of providencia stuartii o4 containing 4 n acetyl l aspart 4 yl amino 4 6 dideoxy d glucose
    Carbohydrate Research, 2004
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Alexander S Shashkov, Agnieszka Torzewska, George V Zatonsky, Aleksandra Blaszczyk, Olga V Bystrova, Antoni Rozalski
    Abstract:

    The O-polysaccharide of Providencia stuartii O4 was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of the pentasaccharide repeating unit was established: [structure: see text] where D-Qui4N(L-AspAc) is 4-(N-acetyl-L-aspart-4-yl)amino-4,6-dideoxy-D-glucose, which has not been hitherto found in Bacterial Polysaccharides. Structural studies were performed using sugar and methylation analyses, Smith degradation and NMR spectroscopy, including conventional 2D 1H,1H COSY, TOCSY, NOESY and 1H,13C HSQC experiments as well as COSY and NOESY experiments run in an H(2)O-D(2)O mixture to reveal correlations for NH protons.

Alexander S Shashkov - One of the best experts on this subject based on the ideXlab platform.

  • structure of the o polysaccharide of azorhizobium caulinodans hambi 216 identification of 3 c methyl d rhamnose as a component of Bacterial Polysaccharides
    Carbohydrate Research, 2012
    Co-Authors: Evelina L Zdorovenko, Yuriy A. Knirel, Olga A Valueva, Vadim V Kachala, Alexander S Shashkov, Iwona Komaniecka, Adam Choma
    Abstract:

    Abstract The O-polysaccharide was obtained from the lipopolysaccharide of the stem-nodulating nitrogen-fixing bacterium Azorhizobium caulinodans HAMBI 216 and studied by sugar and methylation analyses along with 1 H and 13 C NMR spectroscopy. The polysaccharide was found to have a linear pentasaccharide repeating unit containing d -rhamnose and its rarely occurring 2- O -methyl (Rha2 O Me) and 3- C -methyl (Rha3 C Me) derivatives and having the following structure: →3)-α- d -Rha p 2 O Me-(1→2)-β- d -Rha p 3 C Me-(1→3)-α- d -Rha p -(1→2)-β- d -Rha p 3 C Me-(1→3)-α- d -Rha p -(1→

  • structure of the o antigen of acinetobacter lwoffii ek30a identification of d homoserine a novel non sugar component of Bacterial Polysaccharides
    Organic and Biomolecular Chemistry, 2010
    Co-Authors: Nikolay P Arbatsky, Anna N. Kondakova, Marina S. Drutskaya, Sergei A. Nedospasov, Alexander S Shashkov, P. V. Belousov, Mayya Petrova, Yuriy A. Knirel
    Abstract:

    We established a peculiar structure of the O-specific polysaccharide (O-antigen) of a psychrotrophic strain of Acinetobacter lwoffii, EK30A, isolated from a 1.6–1.8 million-year-old Siberian permafrost subsoil sediment sample. The polysaccharide was released by mild acid degradation of the lipopolysaccharide and studied using chemical analyses, Smith degradation, 1H and 13C NMR spectroscopy and mass spectrometry. It was found to contain D-homoserine, which is N-linked to 4-amino-4,6-dideoxy-D-glucose (Qui4N) and is N-acylated itself with acetyl in about half of the repeating units or (S)-3-hydroxybutanoyl group in the other half. The following is the structure of the tetrasaccharide repeating unit of the polysaccharide: →3)-β-D-Quip4NAcyl-(1→6)-α-D-Galp-(1→4)-α-D-GalpNAc-(1→3)-α-D-FucpNAc-(1→ where Acyl stands for either N-acetyl- or N-[(S)-3-hydroxybutanoyl]-D-homoseryl.

  • structures of the biological repeating units in the o chain Polysaccharides of hafnia alvei strains having a typical lipopolysaccharide outer core region
    Fems Immunology and Medical Microbiology, 2005
    Co-Authors: Ewa Katzenellenbogen, Nina A. Kocharova, Alexander S Shashkov, George V Zatonsky, Maria Bogulska, Yuriy A. Knirel
    Abstract:

    Earlier, the structures of the O-chain Polysaccharides of the lipoPolysaccharides (LPS) of a number of Hafnia alvei strains have been established. However, it remained unknown, which is the first and the last monosaccharide of the O-chain. This is defined by the structure of the so-called biological repeating unit (O-unit), which is pre-assembled and then polymerised in the course of biosynthesis of Bacterial Polysaccharides by the Wzy-dependent pathway. Now we report on the structures of the O-units in 10 H. alvei strains. The LPS were cleaved by mild acid hydrolysis and oligosaccharide fractions IIIa and IIIb were isolated by gel chromatography subsequently on Sephadex G-50 and BioGel P-2 and studied by methylation analysis and NMR spectroscopy. Fraction IIIb was found to represent the core oligosaccharide containing a terminal upstream a-D-Glc-(1!3)-a-D-Glc or a-DGal-(1!3)-a-D-Glc disaccharide in the outer region that is typical of H. alvei. Fraction IIIa consists of the LPS core with one Ounit linked by a 3-substituted b-D-GalNAc residue (in strains PCM 1189 and PCM 1546) or a 3-substituted b-D-GlcNAc residue (in the other strains studied). In most strains examined the b-configuration of the D-GlcNAc linkage in the first O-unit attached to the core is the same and in some strains is opposite to that found in the interior O-units of the O-chain polysaccharide. Various monosaccharides, including D-Glc, D-Gal, D-GlcA and acyl derivatives of 3-amino-3,6-dideoxy-D-glucose or 4-amino-4,6-dideoxy-Dglucose, occupy the non-reducing end of the O-unit. � 2005 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

  • The O-polysaccharide from the lipopolysaccharide of Providencia stuartii O44 contains L-quinovose, a 6-deoxy sugar rarely occurring in Bacterial Polysaccharides.
    Carbohydrate research, 2005
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Olga G Ovchinnikova, Alexander S Shashkov, F. V. Toukach, Agnieszka Torzewska, Antoni Rozalski
    Abstract:

    The O-polysaccharide (O-antigen) of Providencia stuartii O44:H4 (strain 3768/51) was obtained by mild acid degradation of the lipopolysaccharide and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, and H-detected (1)H,(13)C HSQC, and HMQC-TOCSY experiments. The O-polysaccharide was found to have a branched hexasaccharide repeating unit of the following structure: [Formula: see text].

  • structure of the o polysaccharide of providencia stuartii o4 containing 4 n acetyl l aspart 4 yl amino 4 6 dideoxy d glucose
    Carbohydrate Research, 2004
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Alexander S Shashkov, Agnieszka Torzewska, George V Zatonsky, Aleksandra Blaszczyk, Olga V Bystrova, Antoni Rozalski
    Abstract:

    The O-polysaccharide of Providencia stuartii O4 was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of the pentasaccharide repeating unit was established: [structure: see text] where D-Qui4N(L-AspAc) is 4-(N-acetyl-L-aspart-4-yl)amino-4,6-dideoxy-D-glucose, which has not been hitherto found in Bacterial Polysaccharides. Structural studies were performed using sugar and methylation analyses, Smith degradation and NMR spectroscopy, including conventional 2D 1H,1H COSY, TOCSY, NOESY and 1H,13C HSQC experiments as well as COSY and NOESY experiments run in an H(2)O-D(2)O mixture to reveal correlations for NH protons.

Nina A. Kocharova - One of the best experts on this subject based on the ideXlab platform.

  • structure of the o polysaccharide of providencia alcalifaciens o22 containing d glyceramide 2 phosphate
    European Journal of Organic Chemistry, 2012
    Co-Authors: Olga G Ovchinnikova, Antoni Rozalski, Nina A. Kocharova, Magdalena Bialczakkokot, Yuriy A. Knirel
    Abstract:

    O-Polysaccharides (O-antigens) are highly diverse glycopolymers present on the cell surface of Gram-negative bacteria, including the human opportunistic pathogen Providencia alcalifaciens. They define serospecificity of strains and are used for the serotyping of bacteria. In this work, a phosphorylated O-polysaccharide was isolated from P. alcalifaciens O22 and analyzed by chemical methods, ESI-MS, and 1H, 13C, and 31P NMR spectroscopy. It was found to contain two unusual components, 2-acetamido-4-amino-2,4,6-trideoxy-D-galactose (D-FucNAc4N) and D-glyceramide 2-phosphate (D-GroAN-2-P), the latter being identified for the first time in Bacterial Polysaccharides. The structure of the trisaccharide repeating unit of the O-polysaccharide was established to be 4)-(D-GroAN-2-P-3-)--D-GalNAc-(14)--D-Gal-(13)--D-FucNAc4N-(1.

  • elucidation of the full o polysaccharide structure and identification of the core type of the lipopolysaccharide of providencia alcalifaciens o9
    Carbohydrate Research, 2011
    Co-Authors: Olga G Ovchinnikova, Antoni Rozalski, Nina A. Kocharova, Nikolay P Arbatsky, Yuriy A. Knirel
    Abstract:

    Abstract Opportunistic human pathogens of the genus Providencia from the family Enterobacteriaceae are serotyped by their O-antigens, which represent the O-polysaccharide chains of the lipoPolysaccharides (LPSs) on the cell surface. In this work, the O-polysaccharide of Providencia alcalifaciens O9 was obtained by mild acid degradation of a long-chain S-form LPS. The structure of the hexasaccharide repeat (O-unit) of the O-polysaccharide containing one d -Gal, two d -Glc, and three d -GalNAc residues was established by sugar and methylation analyses along with one- and two-dimensional 1 H and 13 C NMR spectroscopy. Another degradation product was derived from a short-chain SR-form LPS and found to consist of a core oligosaccharide bearing one O-unit. Its studies by NMR spectroscopy and electrospray ionization mass spectrometry enabled identification of one of the GalNAc residues as the first monosaccharide of the O-unit, whose glycosidic linkage links the O-units to each other and the first O-unit to the core. The core is distinguished by the occurrence of two glycoforms differing in the nature of a lateral monosaccharide, which is either d -Glc or d -GlcNAc. Although composed of common monosaccharides, the O-polysaccharide of P. alcalifaciens O9 has a unique structure among Bacterial Polysaccharides, whereas the oligosaccharide region belongs to one of several core types recognized in the LPSs of Providencia .

  • structures of the biological repeating units in the o chain Polysaccharides of hafnia alvei strains having a typical lipopolysaccharide outer core region
    Fems Immunology and Medical Microbiology, 2005
    Co-Authors: Ewa Katzenellenbogen, Nina A. Kocharova, Alexander S Shashkov, George V Zatonsky, Maria Bogulska, Yuriy A. Knirel
    Abstract:

    Earlier, the structures of the O-chain Polysaccharides of the lipoPolysaccharides (LPS) of a number of Hafnia alvei strains have been established. However, it remained unknown, which is the first and the last monosaccharide of the O-chain. This is defined by the structure of the so-called biological repeating unit (O-unit), which is pre-assembled and then polymerised in the course of biosynthesis of Bacterial Polysaccharides by the Wzy-dependent pathway. Now we report on the structures of the O-units in 10 H. alvei strains. The LPS were cleaved by mild acid hydrolysis and oligosaccharide fractions IIIa and IIIb were isolated by gel chromatography subsequently on Sephadex G-50 and BioGel P-2 and studied by methylation analysis and NMR spectroscopy. Fraction IIIb was found to represent the core oligosaccharide containing a terminal upstream a-D-Glc-(1!3)-a-D-Glc or a-DGal-(1!3)-a-D-Glc disaccharide in the outer region that is typical of H. alvei. Fraction IIIa consists of the LPS core with one Ounit linked by a 3-substituted b-D-GalNAc residue (in strains PCM 1189 and PCM 1546) or a 3-substituted b-D-GlcNAc residue (in the other strains studied). In most strains examined the b-configuration of the D-GlcNAc linkage in the first O-unit attached to the core is the same and in some strains is opposite to that found in the interior O-units of the O-chain polysaccharide. Various monosaccharides, including D-Glc, D-Gal, D-GlcA and acyl derivatives of 3-amino-3,6-dideoxy-D-glucose or 4-amino-4,6-dideoxy-Dglucose, occupy the non-reducing end of the O-unit. � 2005 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

  • The O-polysaccharide from the lipopolysaccharide of Providencia stuartii O44 contains L-quinovose, a 6-deoxy sugar rarely occurring in Bacterial Polysaccharides.
    Carbohydrate research, 2005
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Olga G Ovchinnikova, Alexander S Shashkov, F. V. Toukach, Agnieszka Torzewska, Antoni Rozalski
    Abstract:

    The O-polysaccharide (O-antigen) of Providencia stuartii O44:H4 (strain 3768/51) was obtained by mild acid degradation of the lipopolysaccharide and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, and H-detected (1)H,(13)C HSQC, and HMQC-TOCSY experiments. The O-polysaccharide was found to have a branched hexasaccharide repeating unit of the following structure: [Formula: see text].

  • structure of the o polysaccharide of providencia stuartii o4 containing 4 n acetyl l aspart 4 yl amino 4 6 dideoxy d glucose
    Carbohydrate Research, 2004
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Alexander S Shashkov, Agnieszka Torzewska, George V Zatonsky, Aleksandra Blaszczyk, Olga V Bystrova, Antoni Rozalski
    Abstract:

    The O-polysaccharide of Providencia stuartii O4 was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of the pentasaccharide repeating unit was established: [structure: see text] where D-Qui4N(L-AspAc) is 4-(N-acetyl-L-aspart-4-yl)amino-4,6-dideoxy-D-glucose, which has not been hitherto found in Bacterial Polysaccharides. Structural studies were performed using sugar and methylation analyses, Smith degradation and NMR spectroscopy, including conventional 2D 1H,1H COSY, TOCSY, NOESY and 1H,13C HSQC experiments as well as COSY and NOESY experiments run in an H(2)O-D(2)O mixture to reveal correlations for NH protons.

George V Zatonsky - One of the best experts on this subject based on the ideXlab platform.

  • structures of the biological repeating units in the o chain Polysaccharides of hafnia alvei strains having a typical lipopolysaccharide outer core region
    Fems Immunology and Medical Microbiology, 2005
    Co-Authors: Ewa Katzenellenbogen, Nina A. Kocharova, Alexander S Shashkov, George V Zatonsky, Maria Bogulska, Yuriy A. Knirel
    Abstract:

    Earlier, the structures of the O-chain Polysaccharides of the lipoPolysaccharides (LPS) of a number of Hafnia alvei strains have been established. However, it remained unknown, which is the first and the last monosaccharide of the O-chain. This is defined by the structure of the so-called biological repeating unit (O-unit), which is pre-assembled and then polymerised in the course of biosynthesis of Bacterial Polysaccharides by the Wzy-dependent pathway. Now we report on the structures of the O-units in 10 H. alvei strains. The LPS were cleaved by mild acid hydrolysis and oligosaccharide fractions IIIa and IIIb were isolated by gel chromatography subsequently on Sephadex G-50 and BioGel P-2 and studied by methylation analysis and NMR spectroscopy. Fraction IIIb was found to represent the core oligosaccharide containing a terminal upstream a-D-Glc-(1!3)-a-D-Glc or a-DGal-(1!3)-a-D-Glc disaccharide in the outer region that is typical of H. alvei. Fraction IIIa consists of the LPS core with one Ounit linked by a 3-substituted b-D-GalNAc residue (in strains PCM 1189 and PCM 1546) or a 3-substituted b-D-GlcNAc residue (in the other strains studied). In most strains examined the b-configuration of the D-GlcNAc linkage in the first O-unit attached to the core is the same and in some strains is opposite to that found in the interior O-units of the O-chain polysaccharide. Various monosaccharides, including D-Glc, D-Gal, D-GlcA and acyl derivatives of 3-amino-3,6-dideoxy-D-glucose or 4-amino-4,6-dideoxy-Dglucose, occupy the non-reducing end of the O-unit. � 2005 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

  • structure of the o polysaccharide of providencia stuartii o4 containing 4 n acetyl l aspart 4 yl amino 4 6 dideoxy d glucose
    Carbohydrate Research, 2004
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Alexander S Shashkov, Agnieszka Torzewska, George V Zatonsky, Aleksandra Blaszczyk, Olga V Bystrova, Antoni Rozalski
    Abstract:

    The O-polysaccharide of Providencia stuartii O4 was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of the pentasaccharide repeating unit was established: [structure: see text] where D-Qui4N(L-AspAc) is 4-(N-acetyl-L-aspart-4-yl)amino-4,6-dideoxy-D-glucose, which has not been hitherto found in Bacterial Polysaccharides. Structural studies were performed using sugar and methylation analyses, Smith degradation and NMR spectroscopy, including conventional 2D 1H,1H COSY, TOCSY, NOESY and 1H,13C HSQC experiments as well as COSY and NOESY experiments run in an H(2)O-D(2)O mixture to reveal correlations for NH protons.

  • structure of the o polysaccharide of providencia stuartii o4 containing 4 n acetyl l aspart 4 yl amino 4 6 dideoxy d glucose
    Carbohydrate Research, 2004
    Co-Authors: Nina A. Kocharova, Yuriy A. Knirel, Alexander S Shashkov, Agnieszka Torzewska, George V Zatonsky, Aleksandra Blaszczyk, Olga V Bystrova, Antoni Rozalski
    Abstract:

    Abstract The O-polysaccharide of Providencia stuartii O4 was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of the pentasaccharide repeating unit was established: Download full-size image where d -Qui4N(L-AspAc) is 4-( N -acetyl- l -aspart-4-yl)amino-4,6-dideoxy- d -glucose, which has not been hitherto found in Bacterial Polysaccharides. Structural studies were performed using sugar and methylation analyses, Smith degradation and NMR spectroscopy, including conventional 2D 1 H, 1 H COSY, TOCSY, NOESY and 1 H, 13 C HSQC experiments as well as COSY and NOESY experiments run in an H 2 O–D 2 O mixture to reveal correlations for NH protons.