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An acidic O-specific polysaccharide containing D-glucuronic acid (D-GlcA), 2,3-diacetamido-2,3-dideoxy-D-glucuronic acid (D-GlcNAc3NAcA), 2,3-diacetamido-2,3-dideoxy-D-mannuronoyl-L-alanine (D-ManNAc3NAcA6Ala), and 2-acetamido-2,4, 6-trideoxy-4-[(S)-3-hydroxybutyramido]-D-glucose (D-QuiNAc4NAcyl) was obtained by mild acid degradation of the lipopolysaccharide of the bacterium Pseudoalteromonas sp. KMM 634 followed by gel-permeation chromatography. The polysaccharide was cleaved selectively with a new solvolytic agent, trifluoromethanesulfonic acid, to give a disaccharide and a trisaccharide with D-GlcNAc3NAcA at the reducing end. The borohydride-reduced oligosaccharides and the initial polysaccharide were studied by GLC-MS and 1H- and 13C NMR spectroscopy, and the following structure of the linear tetrasaccharide repeating unit of the polysaccharide was established: →3)-alpha-D-QuipNAc4Ac4NAcyl-(1→4)-beta-D-ManpNAc3NAcA6Ala-(1→4)-beta-D-GlcpNAc3NAc3NAcA-(1→4)-beta-D-GlcpA-(1→.

O-antigen, 2-acetamido-2, Bacterial polysaccharide, 2, 4, Pseudoalteromonas haloplanktis, 3-diacetamido-2, 3-dideoxy-D-glucuronic acid, 3-dideoxy-D-mannuronoyl-L-alanine, 6-trideoxy-4-[(S)-3-hydroxybutyramido]-D-glucose, trifluoromethanesulfonic acid

NCBI PubMed ID: 11042499
Journal NLM ID: 0376536
Publisher: Nauka/Interperiodica
Correspondence: knirel@ioc.ac.ru
Institutions: Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
Methods: GLC-MS, NMR, mild acid hydrolysis, triflic acid solvolysis, borohydride reduction

The initial data on the application of triflic acid was summarized for the isolation of complex monosachharide derivatives and oligosachharides in the structural analysis of various bacterial polysachharides. Solvolysis proceeded selectively and without destruction of the sugars. Varying the temperature and duration of the reaction enabled preparation of oligosaccharides of different sizes.

polysaccharide, structural analysis, bacterial polysaccharides, solvolysis, trifluoromethanesulfonic acid, triflic acid

Publication DOI: 10.1071/CH01181
Journal NLM ID: 0370614
Correspondence: knirel@ioc.ac.ru
Institutions: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
Methods: 13C NMR, 1H NMR, GLC, MS, triflic acid solvolysis

The lipopolysaccharide (LPS) is the major constituent of the outer leaflet of the outer membrane of Gram-negative bacteria. Its lipid A moiety is embedded in the membrane and serves as an anchor for the rest of the LPS molecule. The outermost repetitive glycan region of the LPS is linked to the lipid A through a core oligosaccharide (OS), and is designated as the O-specific polysaccharide (O-polysaccharide, OPS) or O-antigen. The O-antigen is the most variable portion of the LPS and provides serological specificity, which is used for bacterial serotyping. The OPS also provides protection to the microorganisms from host defenses such as complement mediated killing and phagocytosis, and is involved in interactions of bacteria with plants and bacteriophages. Studies of the OPSs ranging from the elucidation of their chemical structures and conformations to their biological and physico-chemical properties help improving classification schemes of Gram-negative bacteria. Furthermore, these studies contributed to a better understanding of the mechanisms of pathogenesis of infectious diseases, as well as provided information to develop novel vaccines and diagnostic reagents.

Lipopolysaccharide, synthesis, lipopolysaccharides, structure, Bacterial, host, O-antigen, O antigen, cell, O antigens, O-antigens, chemical, interaction, cells, PDF, chemical synthesis, biogenesis

Publication DOI: 10.1007/978-3-7091-0733-1_3
Publisher: Springer
Correspondence: knirel@ioc.ac.ru
Editors: Knirel YA, Valvano MA
Institutions: Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia

The chemical structures of polysaccharides and LPS core oligosaccharides, isolated from various Gram-negative marine bacteria from the genera Pseudoalteromonas and Shewanella belonging to the Alteromonadaceae family and gamma-subclass of Proteobacteria, are reviewed. The polysaccharides are distinguished by the acidic character (e.g., due to the presence of hexuronic and aldulosonic acids and their derivatives) and the occurrence of unusual sugars, including N-acyl derivatives of 6-deoxyamino sugars, such as N-acetyl-D-quinovosamine, N-acetyl-L-fucosamine and N-acetyl-6-deoxy-L-talosamine, and higher sugars like 2,6-dideoxy-2-acetamido-4-C-(3'-carboxamide-2',2'-dihydroxypropyl)-D-galac topyranose (shewanellose). Many constituent sugars have various uncommon non-sugar substituents, such as alanine, formic, lactic and hydroxybutyric acids, sulfate, phosphate, and 2-aminopropane-1,3-diol.

Lipopolysaccharide, oligosaccharide structure, O-antigen, polysaccharide structure, Shewanella, Pseudoalteromonas, Proteobacteria

NCBI PubMed ID: 14670708
Publication DOI: 10.1016/j.carres.2003.06.004
Journal NLM ID: 0043535
Publisher: Elsevier
Correspondence: A.V. Savage
Institutions: Department of Chemistry, National University of Ireland, Galway, Ireland, Pacific Institute of Bioorganic Chemistry, Far East Branch of the Russian Academy of Sciences, Vladivostok 690022, Russian Federation

This review is devoted to methods for the selective cleavage of glycosidic bonds. The mechanisms of reactions underlying these methods are considered and examples of their practical application in the structural analysis of bacterial polysaccharides are given. Specific methods for the selective cleavage of polysaccharides, remaining relevant for researchers, include the Smith degradation based on destruction of monosaccharides containing vicinal diol groups, dephosphorylation of phosphate-containing polysaccharides with hydrofluoric acid and the hydrolytic cleavage of glycosyl phosphate bonds in the latter compounds. Non-specific methods, including partial acid hydrolysis, acetolysis and solvolysis with anhydrous organic (CF3SO3H, MeSO3H, CF3CO2H) and inorganic (HF) acids do not make any specific demands on the composition and structure of the polysaccharide and are sensitive to its fine structural features. The review addesses the issue of stability of glycosidic bonds in various monosaccharides to reagents used for non-specific selective cleavage.

structural analysis, Bacterial polysaccharide, selective cleavage, glycosidic bond

Publication DOI: 10.1070/RCR4856
Journal NLM ID: 0404506
Publisher: London: Chemical Society
Correspondence: Yu.A. Knirel
Institutions: N.D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences
Methods: partial acid hydrolysis, HF solvolysis, acid hydrolysis, mild acid hydrolysis, alkaline degradation, b-elimination, Smith degradation, deamination, de-O-acetylation, HF treatment, reduction with NaBD4, triflic acid solvolysis, acetolysis, Li/ethylenediamine degradation, hydrazinolysis, reduction with NaBH4, mild acid degradation, trifluoroacetic acid solvolysis, partial solvolysis with trifluoroacetic acid, de-N-acetylation with hydrazine, part acid hydrolysis, HF solvolysis; published polymerization frame was shifted for conformity with other records.